[jaliberti]

Selectively inbreeding and culling are what give us our beautiful fish from the start. If breeders did not, today, our only choices in bettas would be veil tailed...

Not true, should instead read, "If breeders did not, today, our only choices in bettas would be the wild form, not even veil tailed would have been produced."

Inbreeding,crossbreeding ,in my view/opinion produces weaker specimen's,fishes with unpredictable physiological problem's,unpredictable behaivor's and physical characteristic's,lower fry survival rates,and weaker fish overall.
What once used to be considered fairly hearty species capable of adapting to wider range of condition's,is increasingly becoming an oddity rather than the norm. My two cent's.

That's also my $0.02 ... do I hear $0.96 more?

...Then there's the intentional "defects". I'm not one for any of the various "balloon" fish. But somehow, we all see more and more examples. Who decides? I suppose just about all of us will agree that defects that don't allow a fish to develop, swim or eat properly should be culled...

What about "the intentional defects" which "don't allow a fish to develop, swim or eat" as efficiently as it would without such defects?

Inbreeding of healthy hardy stock does not produce weak or compromised fish. There are small ponds jam packed with inbred wild sail fin mollies...

...those dessert pup fish that lives in little cave pools in the dessert. They've been going at it for hundreds or thousands of years.

Those "small ponds jam packed with inbred wild sail fin mollies" and "those dessert pup fish that lives in little cave pools in the dessert [which have] been going at it for hundreds or thousands of years" are the result of: survival of the fittest, Darwinian evolutionary theory, natural selection, reproductive success, and the survival of the form that will leave the most copies of itself in successive generations, as opposed to a domestic product which is the result of aesthetic qualities which command the highest market value.

 

[jaliberti]

I often see people make this mistake with livebearers. People go to the LFS and select some males and females of the same strain, not keeping in mind, that all the fish in that tank are probably siblings.
Having made that mistake myself with a few fish, I have to admit that deformities were as high as 25% in their offspring. We are talking very good looking fish here (show quality if you wish, with all the horrible things people do to produce those fish).Now I make sure to get fish 2 or 3 months apart if I want a pair.

Those fish 2 or 3 months apart... from the same source... you don't think they are from the same parents? or from the offspring of the same parents?