Here are some common reasons why yeast rolls don't rise: 1. Expired yeast: make sure your yeast is fresh and not past its expiration date. 2. Incorrect water temperature: the water used to dissolve the yeast should be lukewarm (around 110–115 °F). If it’s too hot, it can kill the yeast, and if it’s too cold, it won’t activate. 3. Over-Kneading: don’t over-knead the dough, as it can cause it to be dense and not rise properly. 4. Cold temperature: if your kitchen is too cold, it can slow down the rising process. You can place the dough in a cold oven with a pan of boiling water underneath to create a warm and humid environment.