I've always wondered in these cases -- are we talking about a situation where "failure" means making less money than when you were 35, but by any objective meas

I've always wondered in these cases -- are we talking about a situation where "failure" means making less money than when you were 35, but by any objective measure still bringing in a very good paycheck? ie, Perhaps you used to make $170k, and now you "only" make $130k? Or are we talking about a situation where you get to a certain age and you literally can't find any work?