Symptom: People don't have enough time and resources to fulfill their commitments.
While a project estimate may be realistic in terms of person-hours, people cannot commit every minute of every day to clients' projects. They have other "overhead" tasks that demand their attention, including working with other clients to bring in new business and support past business.
If people are overcommitted, that is, they promise results beyond their available time and resources, they are guaranteed to fail. Remember, it's always better to say no to a new request than to say yes and later fail.
Overcommitment is a symptom of demand that exceeds supply.
Another (more generic) way to state the problem is as follows:
