Schempp-Hirth gliders have a 6000 hr limit before the first inspection, and if IRRC, all Schleicher gliders have a 3000 hr limit before the first inspection.

They can typically be extended out to 12,000 or 18,000 hours with recurring inspections.

However, since most privately-owned gliders tend to fly 100-200 hours per year a 12,000 hour life gives a 60-120 year period. Even a club or commercial glider that flies 500 hours a year still gets 24 years.

Big picture, life limits are not a problem for most gliders or owners.