“I’m worried about our performance in attack. We don’t have a problem with our attitude or concentration, we just need to be more efficient in front of goal,” Koeman told reporters.
Barcelona coach Ronald Koeman cursed his side's profligacy after they drew 1-1 at Alaves on Saturday, dropping points for the fourth game in a row in La Liga.
Barca fired 25 shots at goal but only managed to beat Alaves' brilliant goalkeeper Fernando Pacheco once, when Antoine Griezmann netted early in the second half almost immediately after Jota had been sent off for the hosts.
Barca went behind before the interval when Luis Rioja pounced on a disastrous error from keeper Neto following a mix-up with defender Gerard Pique.
"I'm worried about our performance in attack. We don't have a problem with our attitude or concentration, we just need to be more efficient in front of goal," Koeman told reporters.
"We also gifted a goal to Alaves, but when you create so many chances you can't afford to miss them. If you create that many chances and only score once, it's not good."
The surprise draw against Alaves came after Barca lost 3-1 at home to Real Madrid and were beaten 1-0 at Getafe. They are 12th in the table with eight points from six games.
Koeman could barely hide his frustration at recent results, appearing spiky as he dealt with questions from reporters about his decisions in the game and his touchline demeanour.
"I'm surprised I'm being criticised for the image I gave on the touchline. I think we did everything we could from the dugout and on the pitch," he said.
"In the last 10 minutes we played as we needed to play. If you criticise me for how I appear on the touchline, then we might as well give up."
The Dutchman added: "Of course I'm worried that we've only got two points from the last 12. I think overall we played ok, I'd be more worried if we weren't creating chances.
"But we need to do better in front of goal, with the final pass, the final shot. We cannot afford to squander so many chances, we missed too many."