A GM comes in, prepared, and gives the players options: 3 or 4 or 12 or 30 or infinite options.
The players usually choose one.
This leaves the GM with all the paths not taken. Plus then the GM plans the options for next time, beginning where the PCs left off. And since these options genuinely are options, then, almost by definition, most won't be chosen.
This leaves a lot of extra material. Even if it never gets used, it's there.
So the GM needs a notebook. Full of ideas or stats or places or all three.
It can sit there, and half of it doesn't get used. And it isn't really good for much else, in that form: it's campaign notes. They can't be turned into anything else useful (a book, a movie, a didactic puppet show) without even more work.
So you have it sitting there lonely, between some pages.
Or you can put it up here, on the web. Then people look at your notes--which you pretty much have to make anyway--and talk about them and maybe write back and maybe give you new ideas and suddenly your own backburner and unused ideas bounce back with some new spin on them and you think of a way to use them again. Or maybe you notice someone else has an idea like that, only better.
So the ideas breed. What would've been junk is now alive. And even if you can't use it maybe someone else can.
The point is: GMing and blogging are usefully related in a way that blogging and a million other things you might blog about aren't. I do a lot of things besides play D&D, but for the most part they don't get better or more fun or more efficient when you talk to people about them all day. (Had an art debate today. 5 hours and nothing anyone--including me--said is at all relevant to what I need to do next to the big slippery red and black thing covered in paint lying on its back in front of me right now.)
The point is: this is good. This thing we do is good. Even if you don't get anything out of the last thing you posted, maybe the next GM down does, and maybe they'll repay the favor.
And it doesn't have to be a big deal. I remember reading this old "content lite" post--just the Monsters and Manuals guy writing about his top 10 favorite monsters--and suddenly a whole bunch of things clicked into place. Not because of just that one post, but because I'd been reading everything he was doing--the atmosphere he'd been creating--and then, suddenly, Oh yeah, I see how Mind Flayers are supposed t0 work now. And--I'm sure--to him, it was just some stuff he assumed. Just a different angle on the same stuff is enough.
GMing is...maybe "hard" isn't the word, after all some of the dumbest people you know can do it...but it's a challenge. You set yourself a challenge, or your players do. This thing, however, doesn't have to be. It's just a conversation we're having.
Grab some chicken wings, sit back. "You like Gelatinous Cubes? I hate Gelatinous Cubes! One time there was this Gelatinous Cube and..." and that's all you have to do. Just pull up a chair and talk. Nobody worth a good goddamn is expecting James Joyce here, and if you can write like James Joyce, for Christ's sake don't waste it all on a D&D blog.
If we read you, we know a little about how you roll. If all you have to say today is "I really want to use a giant crayfish this week" that's fucking fine. Maybe that, in the context of everything else you've said, explains more than you think it does. I know if Canecorpus is into giant crayfish, it means something different than if Max is.
This isn't hard. This shouldn't be made hard, you're not being graded, just show up and show us one more way to come at this thing.
Because it is good. It is good to know more. It is good to know how many ways it can be done. It's a hobby. Maybe today's idea is dumb. So what? Maybe someone can turn it into not-dumb. Life is long. Talk.