It took a brilliant second half volley from Watford's Craig Cathcart's to earn the home side the three points and take them top of the Championship table.
"Our aim was to come and stifle them a little bit, like it so often has been. That's the way we've played since we've come in and we don't feel at the minute we're able to be as expansive as we'd like," Rowett said after the game at Vicarage Road.
"We can be at home, our home form is excellent, but away from home; we did it for 35 minutes against Bournemouth and caused them a lot of problems and perhaps couldn't reach those heights today, but it was a more consistent performance.
"We made it difficult for Watford. They're a very good side and they try to play through you and they've got lots of great movement around the edge of the box which means you end up dropping deep and means you can't give space.
"But we hung on in. We were resilient, we kept going, we showed excellent character and just as we were making the crowd get a little bit nervous we conceded a very poor goal from a corner. Secondary phase, we don't react to it, they put the ball in the box and it's a good finish, but we shouldn't do that.
"That's just the small margins at the moment we can't make go our way.
"I'm not too disappointed. Again we've taken a very good side very close and made them a little bit nervous for parts of the afternoon."