plaster life

Anyone know the aproximate life for a standard plaster finish on an in-ground pool?
Mine is about eight years old and its developing some hairline cracks. Nothing is loose, but the cracks are about six to eight feet and extend from the steps across and up to the grouted tile waterline in the shallow end of the pool. I have no idea how to mitigate this. The rest of the plaster is fine.

The pool is overspec as far as the gunite shell and steel, so I'm sure there are no structural issues.

Thanks!

It really depends on so many things that it is hard to say but the range I have heard is 3-20 years. Large, yes, because of the conditions of water, how well the water is kept in balance and how well it was installed. Harline cracks are usually not an issue.