I've recently gotten into The Flash and so I've been reading about his powers.

What I don't understand is why his typical rogues pose a threat - it seems like there should be very little limit to his powers.

 - He can go back in time, so if he loses a battle or the bad guys do
   something, he can go back and preempt it.
 - In the new 52, he can all but predict the immediate future, so he can
   see bad things that are going to happen and stop them.
 - He can phase matter through matter, or let matter pass through him.
   This means he is all but immune to weapons fire.

I haven't read enough of the old comics so I don't know challenges he had. For a guy who can't be attacked, can time-travel and can race around the globe several times in a minute, I can't imagine there is much that could pose a threat.