Installation is about money. A poor installation usually costs you more than you're willing to admit or quantify. A good one saves you more than you're able to admit or quantify.
Many users find installation scary. They don't understand the questions and often can't make sense of what's going on.
Your installation deals with the structure of your architecture. All components and component dependencies must be handled properly.
Make certain your proposed installation process is supported by all of your license agreements.
A general algorithm for installing software is
- Installation data collection and precondition verification
- Postinstallation confirmation
Automate your installation process for internal testing, and make it automatable for enterprise environments.
Test, test, test.