In general, information systems are tools for certain operations or actions. Therefore, failures of using information systems are very similar to failures in using tools: (1) not used in the intended way; (2) put them aside without using them; (3) or because of certain individual or organizational subjective factors.
One can see how important is to engage users in all phases of system development!!
The skill of selling and engaging people is so necessary. Unfortunately, most systems people have the tendency to love systems and to choose to avoid people. [This may be the reason system people become the way they are: self selection] Small wonder that there is a very high rate of failure among system projects.