He won't. People like that don't just give up, unless you completely lost it. Take kobe bryant for example his pedigree for excellence and pushing himself to achieve the top pyramid of his sport is similar to Nadal. They will do anything they can do to win, they work hard and they are mentally solid. Kobe Bryant started getting really bad knees and actually endured a entire season, maybe 2 in which he played every game with bad knees, he ended up going to germany for stem cell surgery and they're all fixed, but he endured that much pain just to win. Nadal is nowhere near that pain, but he is just being more cautious about it. Just because YOU notice a lot of players retiring with Roddick, Ferrero, Chela doesn't mean that someone who is approaching their peak at a relatively median age is going to because the others weren't competing. Nadal being a solid 3 in the world is strong enough to keep winning and to give up now is really really shallow depth of perspective on your part to make such a random assessment. I bet you my salary that he won't retire if you in exchange stop writing threads based on just a shallow perspective with a current trend in mind.