Test and Fix

The model most Engineering companies follow is a simple one:
Design-Test-Redesign-Get extension-Run over budget.

This Engineering Model does not prove profitable for our government that has hired these engineering firms.  A better model would be to Design with all stake-holders having input.  Include all disciplines (Engineers, Training, Human-Factors (someone with wholelistic perception skills), schedulers, CFOs, etc., in the design team and reviews.  This will make the Preliminary Design Phase inversely proportional to the build and test phase.  Creating a wonderful phenomenon called "Meeting the Schedule"

"The power of diversity in groups" grows exponential with each person.   Granted there is a sub-team ceiling that can paralyze the project.  The Project Manager must understand the dynamics of each sub team and the overall Project team.  

A better Engineering Model would be the "T" communication model.  Each subteam is the bottom of the :T" and communicates up to the Stakehoders Design Team.  The top of the "T"  or the Communication Level.
There can be many legs to this model and most projects will have several.   Design and test are not completed until all inputs from stakeholders.  Then most issues will have been resolved.  If your Project Manager has successfully organized and kept abreast of all issues the "kinks" should be picked up by someone without an engineering degree. :)  That is because they will ask different questions.  (Because they don't think they know it all already and the hideous practice of playing the "devil's advocate", which is really just squashing collaboration and stifling free thinking could be avoided.) 

Don't you think someone should be talking about this?