Afghans are aloof and independent. Their hunting origins make them great at problem solving but not following commands.
Basenjis are wilfull and energetic. They get bored easily and are known for not being food motivated, making training tricky.
Chow Chows are very independent and can be stubborn. They need extensive early socialization to be trainable.
Lazy, stubborn Bulldogs have a mind of their own. They'll selectively ignore commands that don't interest them.
Borzois were bred to think independently when hunting. They are intelligent but not obedient or eager to please.
Breeds like Beagles and Coonhounds can be difficult because they get distracted when they catch a scent.
Bloodhounds are affectionate but easily distracted by scents. Maintaining focus during training can be challenging.