Iron

 Here are a few from a school project.  Ergonomics of the handle was the focus of the project.  We did some user testing and some focus group work.  A bit of refinement then went in the modeling process and made some looks like/feels like models.

I went through a number of users. Large/small.  Left/right handed.  They tested three of my models. The one with the most favorable overall feedback was the one chosen for the final model.

Of course several rounds of sketching went along with the user interviews and model making/testing sessions.