Danny Wilson was frustrated that the Blades could not pick up all three points available at Colchester on Saturday.
John Cofie gave the Blades a first half lead, only for Clinton Morrison to level after the break. Late on both Andy Bond and Tony McMahon struck the woodwork but the game finished 1-1.
In his post-match press brief, United chief Wilson said: "We let them (Colchester) stay in the game when we should have put them out of sight. We had so much of the game but took our foot off the gas.
"The lack of concentration is frustrating, it was a soft goal to concede.
"We created chances at will - we now need to turn the good play we've had in recent games into good results - the pleasing aspect of it all is that we are dominating games and getting on top of teams but getting the three points at the final whistle is the be all and end all.
"Whether we win 1-0 or five, six, seven or eight is not important, but getting three points is the aim.
"It was a terrific goal from John (Cofie) and we now that he has that in his locker. He still has a lot to learn, that is one of the reasons why he is with us, but hopefully he can keep getting better."