The Potters went down 1-0 to the Hammers at home and Pulis believes the overall performance of the team needed to improve to gain more positive results.
"We are disappointed with the result, but that is the nature of this league. We are playing against good sides and good players," he said.
"West Ham had a really good spell in the first half and got their goal, although our goalkeeper was not really tested that much.
"We did not have the breaks today but we were not sharp enough either in or around the box.
"At this level you have to take your chances when you get them. But we have to take this setback on the chin and prepare for the next game."