It's not dissimilar from wine aging. Hops, being very volitile, will fade in prominence as time goes on. I'm high abv beers, the alcohol "heat" can also fade, as has happened in a 19% abv beer I brewed. Oxidation can also cause various other things to happen, like enhancing Sherry flavors or Port flavors.

It really depends on the beer and what your looking for. Stouts and barleywine are the most common things to age because they're big and complex and have room, so to speak, to change as they age.

This is also ignoring things like lambics, which some Brewers age themselves and mix things like 3 year old beers with fresh beers before packaging. A place like Cantillon really straddles the line between beer and wine.

Which is to say do not age beers that were intended to be consumed as fresh as possible...which is about 90% of them. If you put away a Bell’s Two Hearted for a couple years you’re going to be very disappointed when you finally open it up.

Typically beers that are high ABV, bottle conditioned, have lower hopping rates (hops oxidize pretty rapidly and throw off some funky flavors) and come from a brewery with stellar packaging processes. Which isn’t to say smaller/less sophisticated brewers can’t make a good beer for aging you just run a higher risk of bad things happening.