Ours is 22 years old and still looks pristine. It is a gunite pool with a DE filter. It was replastered about five years ago. However, a friend with a fiberglass pool had a large crack develope in the shell that could not be repaired. He filled in the pool.

I think you will be hard pressed to find any reliable research that provides a clear representation of how long a concrete swimming pool should last. Most pool builders offer a lifetime transferrable warranty but leave out the definition of what a lifetime constitutes. What if a builder builds a pool on the cheap and his expectation is that the pool should last 15 years and that is what he considers a lifetime. Afterall, it was not defined in the contract. If it is not specified then it is anybody's guess. Concrete pools can experience failure very early on for many reasons. One may be that the pool was not contructed to last a lifetime of 15-20 years but rather a lifetime of 10-15 years. This is a very good question. I would venture to say that not one pool builder on this forum defines the lifetime of their pool structure in their contract but everyone will have an opinion in spite of the fact they have all had pools that have had some level of failure, albeit some more than others for obvious reasons.