Trying to learn tips and tricks on what to look for when trying to understand condition of a playfield.

Here is an example. If I look at a playfield, sometimes it looks really nice, I don't see any ball swirls, the clear coat looks intact on the wood and on the inserts. BUt when I look close, I see cracking between the wood and the insert. What is this called?

If the playfield looks intact everywhere, with little to no chipping in these cracked areas, how bad is that?

What things should I look for when trying to understand how nice a playfield is on one machine versus another?