What are the most frequently made mistakes that lead to the fact that the implementation of time billing software offers results that are opposite to those planned?

Nowadays there are more and more people, who complain about too little time. It is connected with the fact that, first and foremost, we want to make as much as possible. Therefore, we tend to find it hard to build some hierarchy, which we would want to follow in order to gather as much satisfaction as possible. Besides, another crucial complication a lot of people complain about refers to wasting of time, which is relatively simply done for instance in front of the computer.