The 1911.

No other pistol is as revered or despised.
If you get a good one, its a work of art.
A bad one, it will cause ulcers.

We will assume a fully functional pistol, no issues to start with.

Used to be the barrel was rated for 5000 rounds before prime accuracy was gone. (Jacketed bullets)
Nowadays, that’s extended to double or more.
Basically, don’t worry about anything except cleaning it until it stops shooting groups that are decent.

Springs: Swap out your recoil spring every 3000 rounds or so.
The slide can damage itself or the frame if it is too short or weak.
When you swap the recoil spring, replace the firing pin spring, they come with the RS.
If you are so inclined, try different recoil springs to find the most appropriate for your loads.

Hammer springs: Replace when you start getting light hits, or every couple years of hammer back carry. There is no hard and fast rule on these, each manufacturer has different specs and each spring is a rule unto itself.

There are a thousand different things that can be done to a 1911, so we will stick with a GI gun and go from there.

Things to watch:
Magazines, stick to major manufacturers, Wilson Combat, Metalform, Chip McCormick, etc. Cheap junk will give you those results. These are a consumable, replace as needed, but most times they just need a new spring to bring them back to life.

Keep an eye on the plunger tube on the left side, if it starts to come loose, find a gunsmith who can re-stake it. Depending on the gun and how bad it is, silver soldering it in place may be the best option but generally requires a refinish afterwards.

The barrel, link, lugs and bushing.
The barrel lugs can batter and roll over in an improperly fit or hardened gun, watch these.
The link can crack, stretch or break. If it breaks during use, if you are lucky you have a manually operated gun, maybe. Just watch its condition while cleaning.
The bushing can crack and break the retaining tab that holds it in the frame, generally caused by improper fit parts, it will put the gun out of use until replaced. Watch the lug when cleaning, as well as the back of the bushing for warning battering/damage.

Grip screws and grip screw bushings. Oil or grease the threads on the screws before putting them back, if they seize or rust in place, its a challenge to put the bushing back if you’ve never done it before. Don’t over tighten them, just snug.

The extractor.
Ideally, your extractor will hold the case in place with @8-10lbs of pressure. It should not be rough or be untensioned. There are several aftermarket extractors like the Wilson Combat or Brown barstock products that are almost drop in and will normally outlast the owner.

Like any other gun, loose sights, loose pins and screws.
Most 1911 issues are either operator errors (installing junk) or magazine related.

Little things I like:
Recoil buffers. While they do little to actually reduce recoil, they do prevent battering of the slide to the frame. Like any consumable, you need to watch and replace them. I’ve never had an issue with one shredding and tying up the gun, but some have, generally those that don’t maintain their guns.

Guide rods.
Many detest these, I like them for two reasons, I run .22 conversion units on my 1911s, this allows me to swap the entire slide assembly without disassembling it.
Secondly, the recoil spring is not able to rub inside the dust cover, reducing friction. It feels smoother, and any smothness you can add, reducing friction and wear is a good thing.

After that, a 1911 is like a Harley.
There’s little you can’t do to them, not much you can’t fit on or in them.

Leave it as stock as you can, only make changes you need.
The farther you get from GI, the less reliable the gun can get.
Combat loose is fine. You don’t need a target gun, unless you are target shooting.

Me I tell people that a 1911 normally only needs three things, good sights, a good trigger and good magazines. After that, its personal preferences on features, like leather or cloth interior in your car, Ford vs Chevy.

One last thing.
MIM parts.
The 1911 was not designed to use MIM parts, forged or barstock were the way it was designed. Some parts can be castings or MIM, like the grip safety, but others, the critical parts like the sear, disconnector, and hammer should be forgings or barstock parts. Sadly, most manufacturers use MIM in critical areas today.
Me, I junk the internals on all 1911s I get that aren’t pre-MIM. Even new, into the trash can and good reliable, long lasting parts are installed and properly fit.
Cheap insurance, the life I may save may be one of my children’s.

I could go on, but this is a basic post.
Any questions?