When Jeff Beck starts a tour he is on .008". By the time he is on the last date he might be up at .013". It's nothing to do with sound, just how strong his fingers get with constant playing.
With me it how tired my fingers get over the years. I know that there is no way I could play for 2 hours with number ten strings now. The bass E string on my electric guitars are 38s and on my acoustic it is 54 and I don't play it very much.