Every puppy starts out eager and curious, but without the right guidance, that energy can turn into chaos.
Some dog breeds are especially quick to test boundaries: smart, strong-willed, and easily bored when left to their own devices.
Without early training, these dogs can become demanding, destructive, or downright exhausting to live with.
But with structure and consistency, they transform into some of the most loyal and impressive companions you could ask for.
Training isn’t just about obedience; it’s about communication and trust.
The breeds on this list thrive when their minds stay active and their owners take the lead early on.
If you put in the effort from day one, these dogs will repay you with a lifetime of devotion, and far fewer chewed-up shoes.
All information is provided for general interest only.
Consult a qualified veterinarian or certified dog trainer for breed-specific advice.
Photos are for illustrative purposes only.
1. Siberian Husky
Bred to pull sleds across frozen tundra, Huskies possess boundless energy and a fierce independent streak.
Without early training, they become expert escape artists who dig under fences, jump over gates, and ignore your calls completely.
Their stubborn nature means they will test every rule you set.
These dogs need firm, consistent guidance from puppyhood to channel their working drive into positive activities.
A bored or untrained Husky may howl incessantly, destroy furniture, or bolt at the first opportunity.
Their intelligence works against inexperienced owners who fail to establish leadership early on.
2. Rottweiler
Protective instincts run deep in this powerful breed, originally developed to guard livestock and pull carts.
An untrained Rottweiler may become overly territorial, aggressive toward strangers, or dangerously possessive of family members.
Their size and strength make poor behaviour truly hazardous.
Early socialization teaches them to distinguish real threats from normal situations.
Without it, they may react defensively to harmless visitors or other dogs.
Consistent training builds trust and respect, transforming their natural guarding abilities into controlled, reliable protection rather than unpredictable aggression.
3. Dalmatian
Behind those charming spots lies a high-energy athlete bred to run alongside carriages for miles.
Dalmatians without proper training often develop hyperactive, destructive tendencies that exhaust their families.
They may jump on people, chew everything in sight, or become overly excitable in everyday situations.
Their sensitivity means harsh corrections backfire, yet they need clear boundaries from day one.
Skipping early training leads to dogs who cannot settle down, ignore commands, and behave unpredictably around children.
Channelling their stamina through structured activities prevents these problems before they start.
4. Akita
Dignity and dominance define this ancient Japanese breed, originally used to hunt bears and guard royalty.
Akitas naturally assume leadership roles, and without early training, they may challenge their owners, refuse commands, or show aggression toward other animals.
Their loyalty can twist into overprotectiveness.
These dogs require an experienced hand who establishes respect through calm, consistent training from puppyhood.
An untrained Akita becomes stubborn, aloof, and potentially dangerous in social situations.
Their size and strength demand obedience training that teaches them to accept guidance rather than dictate household rules.
5. Chow Chow
That adorable teddy bear appearance hides a fiercely independent personality with natural guarding instincts.
Chow Chows bond closely with their families but often distrust strangers, and without early socialization, this wariness escalates into aggression.
They are notorious for stubbornness that frustrates unprepared owners.
Training must begin immediately to teach them acceptable behaviour around visitors and other pets.
An untrained Chow may become territorial, snappish, or refuse to obey even basic commands.
Their aloof nature requires patient, firm guidance that respects their dignity while establishing clear expectations they must follow.
6. Belgian Malinois
Police and military forces worldwide rely on this breed’s incredible drive, intelligence, and intensity.
Those same qualities make an untrained Malinois a household disaster.
They need constant mental stimulation and physical challenges, or they redirect their energy into destructive, obsessive behaviours like tail chasing or aggressive play.
Without structured training from puppyhood, they become unmanageable, ignoring commands and making their own rules.
Their bite strength and speed pose real dangers when combined with poor impulse control.
This breed demands owners who can provide rigorous training and purposeful activities daily.
7. Cane Corso
Ancient Roman war dogs left their mark on this massive, muscular breed developed to guard property and hunt wild boar.
A Cane Corso without early training becomes a liability, using their intimidating size and protective instincts without discretion.
They may become aggressive toward strangers or other animals.
Their natural suspicion requires extensive socialization during puppyhood to prevent fear-based aggression later.
An untrained Corso will decide independently when to protect, often misjudging situations dangerously.
Consistent leadership and obedience training channel their guarding abilities appropriately, creating a reliable protector rather than an unpredictable threat.
8. Jack Russell Terrier
Never underestimate a small dog with a gigantic personality.
Jack Russells were bred to chase foxes underground, giving them fearless determination and endless energy packed into a compact body.
Without training, they become tyrannical little terrors who bark constantly, dig obsessively, and ignore every command.
Their intelligence means they outsmart owners who fail to establish rules early.
An untrained Jack Russell may become aggressive toward larger dogs, destructive when bored, or impossible to recall off-leash.
Early training harnesses their cleverness positively, preventing the stubborn, unruly behaviour that exhausts unprepared families.
9. Doberman Pinscher
Sleek, powerful, and intensely loyal, Dobermans were specifically created as personal protection dogs.
Their natural guarding instincts can quickly become problematic without proper training to teach them when protection is actually needed.
An untrained Doberman may react aggressively to normal situations, misjudging threats constantly.
These intelligent dogs learn quickly, but that cuts both ways.
They pick up bad habits as easily as good ones.
Early socialization prevents fearfulness and overprotectiveness that plague poorly trained Dobermans.
Consistent training builds a confident, obedient companion rather than an anxious, reactive dog.
10. Weimaraner
Originally bred to hunt large game alongside German royalty, Weimaraners possess relentless energy and intense attachment to their families.
Without early training, they develop severe separation anxiety, becoming destructive when left alone.
They may chew through walls, doors, or crates in their distress.
Their intelligence and sensitivity require gentle but firm training methods from puppyhood.
An untrained Weimaraner becomes hyperactive, jumps on everyone, and ignores recall commands during outdoor adventures.
Teaching independence early prevents the clingy, anxious behaviour that makes them challenging companions for working families who cannot provide constant attention.
11. Bullmastiff
Gamekeepers bred these gentle giants to tackle poachers silently, combining the Bulldog’s tenacity with the Mastiff’s size.
That history means Bullmastiffs naturally guard their territory and can become overly protective without proper socialization.
Their massive size turns any aggressive behaviour into a serious problem.
Early training teaches them to accept strangers and other animals peacefully.
An untrained Bullmastiff may become stubborn, refuse commands, or show aggression when feeling threatened.
Despite their calm appearance, they need consistent guidance from puppyhood to channel their protective instincts appropriately and respond reliably to their owner’s direction.
12. Australian Cattle Dog
Developed to herd cattle across vast Australian ranches, these dogs possess tireless energy and a strong desire to control movement.
Without training, they may nip at running children, chase cars, or herd family members aggressively.
Their intelligence becomes a problem when directed toward unwanted behaviours.
An untrained Cattle Dog grows bored easily, leading to destructive chewing, excessive barking, or obsessive behaviours.
They need jobs to do and clear rules to follow from puppyhood.
Early training redirects their herding instincts into appropriate activities, preventing the frustrating, mouthy behaviour that makes them difficult family pets.
13. Presa Canario
Spanish farmers created this formidable breed to guard livestock and property with unwavering courage.
Presa Canarios naturally assume dominant roles, and without experienced training, they become dangerously aggressive and uncontrollable.
Their bite force and size make any behavioural problems potentially life-threatening.
These dogs require firm, consistent leadership from the moment they enter your home.
An untrained Presa may challenge family members, show aggression toward strangers or animals, and refuse commands.
Early socialization and obedience training are absolutely essential to prevent the territorial, dominant behaviour that has given this breed a controversial reputation.
