There are a lot of developers building a software product for internal purposes of their companies (not for sale). If large enough, the developers do not support established product, there are some people. The question arose — how to convey designed FOR to support, that would on the one hand not to spend twice more time than the development itself, and on the other to support not escalated every second question to the developers, as it is not able to solve it yourself.
While born only:
The existence of the user.
The questions, the answers to which are not in the manual, you receive a timely response and is included in the manual.
The lack of mass incidents related to flaws of the system (not the subsequent improvements, namely, the original).
The availability of trained support staff.