Like I said, it’s easy. Start at the problem and work backwards to find the root cause, continually asking, "Why?" Repeat it over and over until the root cause of the problem becomes apparent. It’s kind of like trying to explain something to a kid – “You have to go to bed.” “Why?” “Because it’s time.” “Why?” Yadda-yadda-yadda. You get the picture.
Here’s an example:
1. Why is our client ready to drop us? Because we didn’t deliver our product when we said we would.
2. Why didn't we deliver our product when we said we would? The job took much longer than we thought it would.
3. Why did the job take so much longer? Because we underestimated the complexity of the job.
4. Why did we underestimate the complexity of the job? Because we made a quick estimate of the time needed to complete it, and didn’t list all the steps needed to get it done.
5. Why did we make such a quick estimate? Because we were running behind on other projects and didn’t clearly review our time estimation and procedures.
From there you can make plans to ensure that no matter how behind you’re running you have a process in place to properly plan and review time estimations and procedures.