Fast concept sketching is a specific intermediary help that perhaps is ommitted by quite some designers alltogether. We use a 3-step journey through concept development :
Concept work starts with written concept outline. If story driven, the storyline comes in. If an educative project, it's the interpretation path.
Then, fast concept sketching is used to visualise basic ideas before going into full concept drawings. Reason: using budget at the right moment. Fast concept sketching is a day-to-day core team work, used for internal client and team communication only. Usually, a lot of such fast concept sketches are stored 'in the box' for us, to remember the processus of thinking. Ideas are reviewed and definitive concept artist(s) selected and proposed.
On approval of the basic idea, extensive concept outline & concept art is produced. Graphic artist production is taking over the ideas selected earlier from fast concept sketching, and bringing them professionally to life, in their personal style. That's why the second step in the concept development also includes the choice of the actual concept artist, to be shure the basic concept will match perfectly with the artists style.
Following fast concept sketching, the development also splits up into full concept art work & early technical outline (looking after space use, listing of nessessary resources and eventually technical imagineering requirements, all in view of early budget control. )