Re-plaster white with "mottled" finish

[SoCal]

We had pool replastered and the job looked bad after the water was in and the pool was cleaned a few times. It was plain white, same as before, but it had a very dirty look to it immediately. We kept blaming the pool man and he kept telling us it wasn't anything he was doing. Because we would not be home when the pool man cleaned the pool we were not aware of just how badly the coloring was. Our old pool lasted more than 30+ years and never look as bad as the new one. I understand that "colored" pools will sometimes within even a short time(less that a year) have problems. But not the white pools. My thinking is it was either a bad mix or application, either way the workmanship. What else would cause a white pool to look dirty, mottled, etc almost immediately after being put on line?? Any help or clarification would be greatly appreciated.

[Guest]

plaster still fresh and not fully cured yet

bad water balancing with new water fill

dodgy fill water

incompatible chemicals for a new surface