In The Flash, the Speed Force is a Story-Breaker Power, so these have to exist to provide the speedsters challenge in the comics.
- Firstly, anything that can drain energy or slow things down, such as Captain Cold's gun, the Turtle's 'slow field', or the Negative Speed Force and Still Force, will drain the speedster of their speed.
- Secondly, while they have Super-Reflexes, these only kick in when the speedster is actively using their powers (or in Wally's case, he's bored). If they're not moving, they can be caught by surprise, knocked out, tied up, distracted, or shot. Similarly, the Flash Family as a whole are rarely using their top speed in everyday usage, so while they could outrun an attack, that doesn't guarantee they'll succeed if they don't realize how fast its moving.
- Good speedsters like the Flash are morally upright individuals. As such, they're reluctant to use their powers in ways that could seriously harm their enemies, and generally pull their punches. This means they don't always use the appropriate level of force against an enemy if they don't know what's needed; its quite often shown that when they fight someone new, or an enemy who's since Took a Level in Badass since their last fight, they get their asses handed to them because they weren't pushing themselves.
- On the inverse, Eobard Thawne and the other Reverse-Flashes are sociopaths who want to cause more harm than is needed, so they often avoid actually killing people when they could instead break them. This means they often beat the Flash senseless, but then try to pull a Forced to Watch by attacking their loved ones or stop to gloat and rub their victory in their face, and these often give the Flash time to get their Heroic Second Wind and escape. Even when attacking their non-speedster loved ones, they like to draw out the kill and underestimate how resourceful or how Badass Normal Iris, Linda, or Piper can be.
- Individually, the Flash Family have a couple personal hang-ups that also keep their powers in check.
- With Wally West, unlike the previous Flashes, he's not a genius scientist, so he doesn't know the complex scientific ways to implement his power that Jay and Barry could pull off, meaning he's often thinking on his feet and improvising rather than being able to come up with a quick science trick. Its also shown that Wally suffers from some form of depression disorder, and when he's in a funk, he's more likely to make mistakes or be distracted, and his powers appear less effective. Its clear that there's a psychosomatic aspect of the Speed Force, so when Wally was suffering from an inferiority complex after Barry's sacrifice, his speed dropped to below the speed of sound. Even after coming to terms with it and becoming the Fastest Man Who Ever Lived, he's still vulnerable to his speed dropping thanks to his mental state.
- On the inverse, Barry is far more methodical in his thinking. While he's still got Super-Reflexes, he's sometimes slow to act because he's busy working out the most practical and scientific use for his speed. As well as that, because he's a rationalist who can't bring himself to see the Speed Force as anything outside a scientific anomaly, he's far more limited in what he can do with it, only able to use it for pure Super-Speed and any tricks more complex than that are just creative scientific applications of it. This also means he's the slowest of the Flashes (Depending on the Writer, as it goes back and forth on who is faster), and has the least range of creative uses for it.
- Jay Garrick is the most well-balanced, being creative, open-minded, and a genius scientist, but he's also pushing 90. He's got the same level of Super-Speed as Barry, but he doesn't have his or Wally's stamina and when he gets hurt, he takes far longer to recover; Wally is shown recovering from breaking both legs in about a week, while Jay takes months to recover from his leg being twisted by Thawne and occasionally demonstrates a weak leg after the fact.
- Bart, simply, has Attention Deficit... Ooh, Shiny!. He's far more easily distracted and often forgets what he's doing. Getting him to focus is one of the biggest difficulties the other Flashes have.
- Johnny Quick and his daughter Jesse had to activate their Speed Force connection by reciting a 'speed formula', 3X2(9YZ)4A. While the others could run fast by just willing themselves to, they had to get it into their head, and its shown occasionally they had to keep doing it or the speed would fade. While they had some additional usages for it (they could fly, and Jesse also had similar temporary Super-Strength thanks to her mom's similarly activated Super Strength), this unique method of power usage meant they could be cut off from their speed if they're interrupted before finishing it.
- As well as that, Jesse had an even bigger chip on her shoulder than Wally when it came to living up to legacies, as she had a "Well Done, Son" Guy dynamic with both her parents, so like Wally her powers were often affected by her mental state. And as she was more a student than a sidekick/partner to her dad, she had comparative less experience when she 'took over' the Quick legacy, all while jumping into fighting villains who were already prepared for how to fight speedsters. She often got her ass kicked by the Rogues who knew all the tricks a Flash could pull off, but had none of the experience of fighting a Rogue herself.
