I've been playing drums since I was about 7 years old, and trying to record and mix them for about 10 years or so.
The problem with drums is that 99.99999999999999% of drummers just aren't that great (including me). Most drummers aren't even capable of hearing their lack of tightness, let alone improving it. And I'm talking about drummers who can stay in time with a click all day long, but just aren't tight enough (with the groove, not the click).
Then you've got the fact that most drummers hit their cymbals waaaay too hard. For recording drums, you want to play your drums incredibly loudly, but have the lightest of touch on your cymbals. (Guess what? This also applies to live music too). It doesn't help that many of the major-brand cymbals manufactured today are an order of magnitude too thick and heavy, even for the most hardcore of thrash death metal.
(The reason for this is: when you hit a cymbal on its own in a drum store, the thicker brighter cymbals will sound better. But when you play with a group, and listen from a distance, the darkest, thinnest cymbals will actually sound better around 80% of the time)
(BTW, there are great drummers who will not follow the rules I listed above, but will have fantastic dynamics. The point I'm making is about listening to the dynamics rather than following the rules).
If you go to any venue with amateur bands playing live music, I GUARANTEE you will hear a drummer smashing the hell out of his thick heavy hi hats, and barely even stroking his snare drum.
That brings us neatly to our next problem: many drummers literally don't even have the technique to play the snare loudly enough on the 2 and 4 (I'm talking about pop / rock / funk here, not jazz / swing).
What you'll find is vast hordes of arm wavers who put huge amount of effort into playing loudly and looking like a monkey, and then a small group of pros (the 0.00000001%) who can play their snare on the 2 and 4 about a billion times louder than the former group, without even moving their arm at all: just a small flick of the wrist and snap of the fingers. Look at Dennis Chambers videos to get an idea of what this looks like.
Then after that, for live drums, the overhead mics are key and give the main sound, and the close mics are really just for making individual drums sound more punchy.
Then compression (but not always!) for enhancing punch (medium attack to let the transient through, release time set to move in time with the music), limiting / fast compression / clipping / distortion for controlling dynamics or changing the tone or timbre.
Then EQ: too much to go into here, but no matter how many tutorials you read or watch, it WILL take you ten years of actual practice to get good at EQ, there are no shortcuts. (If you do it all day every day, it might only take a couple of years). This is the hardest part of mixing anything.
Then finally some reverb: Short ambient dense & diffuse reverbs with no predelay for creating a sense of space (particularly on drum samples or drums recorded in a dry room), and a bit of long reverb depending on the style you are going for.