I have this happen to me every now and again, when Im fighting a dude, and you can blatantly tell they're not fighting.  
 
I will usually just sit there and wait until I get a response from the character..  Dunno, I guess its the "honorable" guy in me...  
 
Occasionally (since I have young children), I may have to completely walk away from my controller during a live fight, even if just for a second.  9 out of 10 times... the round ends in a perfect... (for the opponent of course. ) 
 
I mean, it kinda sux, but on the other hand, there is always that 1 time where a guy im fighting doesnt attack, and waits for a response from me.
 
Dunno, I guess it seems like the "RYU-ISH" thing to do..  
 
thoughts?

i give it about 15 seconds. then ill use you for combo practice.

I will wait about 20 seconds. If there is no response, I work on one framers.

I was playing a guy who missed his ultra pretty badly. I taunted several times instead of finishing him off. He quit playing... Just let his character sit there. I felt mean. :/

" I was playing a guy who missed his ultra pretty badly. I taunted several times instead of finishing him off. He quit playing... Just let his character sit there. I felt mean. :/ "

If it's a random, no.  If it's a friend, yes.
 
EDIT:  I should have worded that better.  If it's a random, I will kill him.  If he is a friend, I will give him a little bit before I kill him.

I'll usually wait a while. I often have my laptop sitting next to me while I play, so I don't have a problem doing something else while they get back. If I notice it getting close to the end of the round though I'll give it to them.

I just wait for him until he responds until there are only 20 seconds left in the timer, then I'll start doing some combos and try to finish him off to win the round or match hehe!

Definitely go in for the kill, but it's not pretty.
 
Crouch + Hammering Light Punch as fast as possible = CROTCH TREATMENT!

I've never been in that situation myself. 
 
But I've given up before, at the end of round 2, because I didn't feel like I could get a punch in. It's happened once or twice.

I just kill them.  If they can't get it together and have a working controller, I don't see any reason to let them win.
Edit:  I'm talking about ranked matches here.  Against people I know, I'd wait.

I wait till there are a few seconds left then hit them once and wait for the time out win

I usually teabag and taunt for a good portion of the time-limit, if there's no reaction I end them like John Lennon.

I don't wait, I jump in and kill them. Don't have time to wait on the battlefield.

If this were a real street fight and someone just stopped fighting, I'd fucking pummel them. 
 
The same goes in the game. 
 
And if it's a friend, I beat 'em twice as hard to make sure they don't do it again!!!

If I'm playing as Fei Long, I almost always start round 1 with a HP Rekka Ken to catch the dude off-guard.  So if he's not paying attention, it's not my problem.  On the other hand, I usually give up if I'm getting totally spanked in a round and have no chance to win.  Drives me nuts when the other dude just waits around to see if I'm going to do anything.  Hint: I'M NOT!!!!

I'm pretty easy going, so I wait. Not like a target that doesn't block is much of any practice, anyway.

" I wait... if no response, i quit. Don't really care for target practice. "

If they're randoms I'll wait maybe 5 or 10 secs then kill them because I want t fight someone real. If they're a friend I'll wait.

" If it's a random, no.  If it's a friend, yes.  EDIT:  I should have worded that better.  If it's a random, I will kill him.  If he is a friend, I will give him a little bit before I kill him. "

usually i wait about 20 secs or so, then just finish the fight to move on

I wait about 10 seconds then start doing jabs and dicking around

" I wait about 10 seconds then start doing jabs and dicking around "

" @Jeffsekai said:

" I wait about 10 seconds then start doing jabs and dicking around "

The sad thing is you lose even when they are not there to play :( "

" @Jeffsekai said:

" I wait about 10 seconds then start doing jabs and dicking around "

The sad thing is you lose even when they are not there to play :( "

Depends on my mood.

" I don't wait, I jump in and kill them. Don't have time to wait on the battlefield. "

If you stop responding mid-match, you're wasting MY time, so I'll kill you. 
 
Don't be a scrub, play to win.

If they started a game and pressed ready im assuming they're ready, I could care less if they had to do something when the match started

it in all honestly depends on who they are, how they were playing before they stopped and what character they use