When you overload your resources with work, the project finish date may look good, but it's bogus, because your resources are overallocated. In other words, giving people 20 hours' worth of work a day doesn't mean they're going to do it. Resources who don't have enough work cause a whole other set of problems. Besides distracting the people who are working full out, these resources could cost money without delivering results—like the networking consultant who sits idle while your IT staff puts out the fire in the server room. The ideal workload is when you assign your resources at exactly—or as close as possible to—the amount of time they have to give.
Before you can call a schedule done, you must balance workloads so your assigned resources (people and equipment) are busy, but not burning out. The first step is recognizing the problem, and Project makes it easy to find assignment peaks and valleys.
Then, you have to correct the workload imbalances you find. Before you look for additional resources, you can try adjusting work contours (the pace at which work ramps up and down during an assignment), delaying assignments, or leveling resources (rescheduling tasks so that assigned resources aren't overallocated). Of course, you can always look for other available resources, or ask resources to work more. This section describes how to spot resource allocation issues, and several ways to fix them.
Assigning resources to tasks ...