Ok, then lets stop breeding danes; years taken off their lives just to be big.
dalmations; deafness from inbreeding.
shar pei's; respiratory defects.
pugs; same as shar pei's.
dogue de bordeaux, most mastiffs; all of the above.
Sealyham Terriers; brittle bones and bad backs.
The list goes on. Inbreeding occurs in nature, plain and simple, and these problems would eventually occur, just over a longer period of time.