If you don't damage the voice coil by overheating it, nor damage the suspension by overexcursion, they will last decades in normal, or even fairly heavy use such as in a studio monitor which is likely going to get many hours more per week than it would in domestic use. If you're not doing either, stop worrying about it. There are drivers like Tannoys that still command large $ even though they are 40 years old, and I've had enough through my place, and measured them to know they're still fine.
EDIT: older foam surrounds tend to deteriorate, but newer ones age much better and they are generally cheap and easy to replace.
“You are not special. You are not a beautiful and unique snowflake.” Chuck Palahniuk