This feature is primarily for using Jenkins as a cron replacement, and it is not ideal for continuously building software projects . When people first start continuous integration, they are often so used to the idea of regularly scheduled builds like nightly/weekly that they use this feature. However, the point of continuous integration is to start a build as soon as a change is made, to provide a quick feedback to the change. To do that you need to hook up SCM change notification to Jenkins .
So, before using this feature, stop and ask yourself if this is really what you want.