If a nylon string was three years old for example would be just a prone to breaking as a steel string. Three years is a long time for nylon. After one month, two at the most, the basses don't sound as good and have to be replaced. The trebles will sound okay for a few months, but they have to be replaced, too.

How long do nylon strings last?

Some people do not sweat much and keep their fretboards squeaky clean and the bass string coils are free of detritus. For a non-professional, hobbyist player of the classical guitar, a set of nylon strings will last two months or about 80 hours of playing before the sound noticeably degrades.

Do nylon strings break often?

If you use light strings and do a lot of string bending, you'll pop more treble steel strings. But if you don't play particularly hard, you'll find that nylons are more likely to just passively break for no apparent reason.