3. Glen of Imaal Terrier
Terriers make a great dog breed, but this breed is no longer owned by many. The primary reason is because of its inability to handle warm climates, which means it needs to be in northern hemispheres. In addition, the small breed size is not always welcoming for families who desire a watchdog to safeguard the house. While many may desire these qualities, this breed has simply not been the best choice over recent decades.