In proof just how impeccably high the standards at Bayern are, Sammer has demanded the side gets better after a goalless UEFA Champions League draw at Shakhtar Donetsk on Tuesday.
Most clubs would be pleased with an away draw and Pep Guardiola's men now know victory at home will be enough to progress to the last eight of Europe's premier club competition.
"Everyone can see we have room to improve before we reach peak form, and that's the message for the next few days," Sammer told the club's official website after the Shakhtar draw.
"We have to shift up a gear. Our performance today was okay, but it wasn't great ... we need to improve."
Bayern thrashed Hamburg last Saturday, with Arjen Robben, Thomas Muller and Mario Gotze all scoring doubles. The win was the club's biggest in over 30 years and will have Paderborn's defence on high alert.
After a bright start, Paderborn's maiden Bundesliga season looks like ending in a relegation fight.
Gotze scored twice in that victory, while Muller and Robert Lewandowski also netted as the sides met in the Bundesliga for the first time.
