As the analyst proceeds with step 2, there are continuing opportunities to
use preconceived ideas, or ideas that form as information is obtained.
For example, if a customer complains that his engine made a loud
knocking noise and locked up, the analyst may have a preconceived idea
that low oil level caused insufficient lubrication. But as more facts are
gathered he may find that the oil pump gears failed and oil flow stopped.
Using preconceived ideas is dangerous because it can lead in the wrong
direction and cause wrong conclusions.