system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] How can the Flash lose?

I've lived all over, and seen a bunch of these so-called "superheroes" fighting against villains and each other.  There's one, calls himself "The Flash", who as I understand it has the ability to make himself super fast through something called the "Speed Force" (I overheard him telling Superman about it).  From what I understand, Speed Force is pretty insanely overpowered; how does anyone beat him?  Can't he punch someone so fast that there's a black hole or something like that?  How could anyone match that?
gpt
A lot of people make the Flash seem more powerful than he really is, often citing speed feats as if they're something he can do at the drop of a hat, rather than exceptions that he can only do under extreme circumstances or with outside help.

For instance: People cite his ability to run faster than instant teleportation. They forget that he did that by stealing the speed of two different planets, one of which consisted entirely of sentient radio waves.

His so-called 'infinite mass punch', while powerful, still wears him out a bit to use. And if he used that on anyone short of a Martian or a Kryptonian, it would instantly kill them. Hell, even punching people at the speed of sound would tear their heads off. Not what he's aiming for. He's gotta slow down.

Yes, the Flash is insanely fast. Faster than Superman. But his most insane stunts are done through circumstances that, sometimes, just can't be repeated. Hell, every time he pushes lightspeed, he risks being absorbed into the Speed Force. If he didn't have an anchor, he'd instantly be lost. And the faster he goes, the harder it is for him to hold on to his 'anchor'.

If it were otherwise, he'd be an untouchable speedgod that would never be bothered by his Rogue's Gallery. If you want a textbook on how to beat the Flash, look towards his most frequent foes. Yes, they lose a lot, but they also win quite often. Even if you only count 'winning' as 'escaping'.

Let's look at a common tactic of Captain Cold, Heatwave, and (sometimes) Weather Wizard. The fastest man alive can only run if he's got good enough traction. We've seen them slow him down by messing with his footing, melting it or freezing it.

Another trick often used by Heatwave, Captain Boomerang, Weather Wizard, and the Trickster? Distractions. They throw out things that can cause collateral damage, causing the Flash to stop, take care of that, and wait to see if the problem's fixed before chasing them. That's the genius of it, he can perform all of the actions he likes in a second, but he's still got to wait thirty, forty seconds for that to work, and then more to see if it'll work/if there's any secondary problems.

tl;dr: The Flash isn't as insanely overpowered as everyone thinks (though that very reputation can do a lot to discourage crime) and even if he was, there's ways to force him to slow down.