At halftime, Georgia's Tech's lead was Carolina's biggest halftime deficit ever at the Dean Smith Center.
"I apologize to all the North Carolina fans that care about our basketball program, former players, everybody who cares about us cause we stunk it up tonight," said Williams during the opening statement of the post-game press conference.
The Tar Heels did not make a field goal until 6:50 left in the first half.
"It's gotta be my responsibility. It's the most negative I've ever been about myself, most negative I've ever felt about a team. We weren't ready to play," said Williams.
UNC's comeback falls short against Georgia Tech, 96-83
Garrison Brooks had a career-high night with 35 points.
The Heels cut the deficit to single-digits but never enough to take the lead.
"Most disappointed, most upset I've ever been in my life coaching a basketball," said Williams.
"Between now and the next game, I've got to figure out how to become a better coach than I am right now," he said.