Derek Adams blamed individual errors, following City’s 2-1 loss to Tranmere Rovers.
The Bantams fell to defeat on Merseyside after the hosts scored twice in quick succession to send City home empty handed.
Adams was frustrated by the number of mistakes that caused his City side to surrender a 1-0 lead, and suffer their first defeat in seven.
He said: “We looked very comfortable in the first half, and the only time we were causing ourselves problems was when we made individual errors - and that happened a number of times.
“We made a lot of errors that gave them opportunities in the game, and you are not going to get away with it for so long.
“The only times we looked to be in any danger was when we made the mistake, and we have got to eradicate that.
“It is really frustrating.”
Adams was disappointed to lose three key players to injury, having lost top goal-scorer Andy Cook just last month.
Charles Vernam, Lee Angol and Caolan Lavery were all forced off due to injury and the Scot suggested this limited his side's chances of getting back into the game.
He added: “It is hugely disappointing to have three players go off injured in any game.
“It definitely changes the flow of the game. You have worked on a gameplan to have certain players playing in their positions and, when you have to replace them, it is difficult to get back into the game.
“By the time all three players had come off, we are 2-1 behind and trying to get back into it.”