Joachim Low says Germany have work to do ahead of the European Championship after labouring to a 2-1 win over Georgia on Sunday.
The world champions qualified for the finals in France as Group D winners but only after losing their penultimate game against the Republic of Ireland and then laboring past Georgia 2-1 with a late Max Kruse winner.
Low's men were becoming frustrated in their final qualifier in Leipzig after failing to make early dominance count and seeing Jaba Kankava cancel out a Thomas Muller penalty with a stunning strike.
"We are like a boxer at the moment. We're landing punches but they're not knocking the opponent out," Low said on uefa.com.
"We won the group and can be happy about that, but I am not satisfied with the last two matches.
"It will take some hard work to get back to the level of performances of the World Cup but there is a long way to go until the finals and we know that a long period of preparation will do us a lot of good."
He added: "We know that is not what we demand from ourselves. Not the way we are currently operating in front of goal. We made our own life difficult.
"We sang the same song as in Ireland. Three, four huge chances early on and then the mistakes start creeping in.
"First of all, we are satisfied with the qualification but not satisfied with our last two games. That is not our standard. We have work ahead of us."
The hosts should have gone ahead with one of three opportunities that fell to Marco Reus early on but the attacking midfielder failed to score as did several of his team-mates in a one-sided first half in which Germany had more than a dozen attempts on goal.
"Marco usually does not waste them but today he had three huge chances early," said Low. "He has the quality but tonight we did not show we can make this big number of chances count."
Low will look at the make-up of his team and try to modify their approach ahead of the finals next summer.
He said: "Tactically there are a few things we need to consider. Our style of play will remain mostly the same but there are some details that need adjusting.
"It is not our style to send long balls into the box. It would be better to approach the opponents' goal with combinations.
"But in France we will meet teams that will attack us, not like some of the defensive teams we have met recently."