Katt Williams Cancels Concert 15 Minutes Before Showtime

At this point, if you buy tickets to a Katt Williams show ... you should surprised if he shows up.

The train wreck "comedian" bailed on yet another performance last night -- this time in Kansas City -- with the announcement coming just 15 minutes before it was scheduled to start.

The audience was given no reason for the cancelation.

Williams didn't show for concerts last week in Houston and New Orleans, but did make it to his show November 30 in Seattle ... where he whipped a fan with his microphone.