How long do polishing compounds last?

[mcpp66]

Hello, it's been a little while since my last post. Anyhow, I have some Meguiar's Ultimate Compound, M105, M205, and Menzerna PO85RD that are a few years old. Do these products last or do they tend to go bad? I've been out of the game for a while and have a potential opportunity to do some paint correction soon and am hoping I'm not going to have spend money on fresh polishes. I know the only way I'll probably know for sure is to do a test, but I thought I'd start here just to get some general opinions. Thank you.

[Paul A.]

I've had several over recent years when i wondered the same thing you are asking. The best advice i read was to shake them up real good and see if they return to a consistency that can be worked. Some have and some have not. The latter i tossed and am still using some that passed the test.