I read,after a cycle you should expect to lose 90% of your gains, what's the point?

[lovbyts]

So why would you cycle when at or past your genetic limit? Most people look at their aesthetic best when at their genetic limit and with low body fat. Why risk your health just to go over that genetic limit? Seems rather pointless to me.

I have a SIMPLE example.
Speed limit is 70 mph most everywhere. Why make cars that go faster than 70 or 80 mph? Why modify your car or bike?????