Why did the top layer come off the steps?

My next door neighbor's house is built into the rear of a hill, so the
back opens up at ground level and the front is one story up, with cement
or concrete? steps.

They needed repair and looked quite smooth after the rapair was done,
but within a feew years the top layer chipped off.

His son tells me it's because they used salt on it before they should
have. Right?


OTOH, it's the risers too, not just the horizontal parts.

Would salt have damaged the risers?


I had assumed he hired someone who didn't know how to do a good job.
??

It actually looks better this way. It was too smooth, imo, but now with
the rounded rocks that are showing now, it looks like some medieval
castle's steps.