Too much rubbish and ignorance in here about purebreds to even start and reply to it.
But for those talking working dogs, lets not forget how many of those get shot/put down or dumped at country pounds for lack of working drive or ability too. Just like racing greyhounds. Working line bred does not guarantee working drive or ability, just like show line bred doesn't guarantee perfect type either.
These are living creatures, not cars or electrical goods. What is with this expectation people are developing for guarantees on everything about them?