The conclusion is more than just a summary, however, because you also get to speculate on how to do things better. For instance, it could be the case that your hypotheses weren't supported, but you really believe that the relationship exists. You could then bring up issues of validity and reliability. You could state that future research should ask more or different questions. You could state that future research should use more variables or add different variables. You could argue that the sample was poor. It's your opportunity to brainstorm on how future research should be done.