I worked in a garage that offered lifetime brakes on cars everyday. Think of it this way - what other jobs go on in a basement. Say you call for an issue:
You:Hi I am having an issue with my foundation - you guys fixed it xxx years ago so I need you to fix it ASAP.
Company: I will have someone come out and look tomorrow
Company arrives on site
Company: We inspected the area - we are going to fix it and do right by you as a customer, however we did notice a water intrusion issue in your basement - that indicates to us it wasn't our workmanship that was an issue. What I can do is warranty it this one time but you really need someone to fix the drainage issue... by the way we do that sort of work, my guys will already be here fixing the foundation for you so I can offer you a special price of 1999.
If there is a warranty there are stipulations on both sides, remember that. They want to come back because at some point it means more revenue for them.
I could be way off base, I am just a retired mufflerman ; )