In movies, film and Hollywood, costume, hair and makeup test footage is very important. It helps the production team get a good look at how a character will look on-screen. Here's a look at some of the behind-the-scenes makeup/wardrobe test footage for the television series, "Star Trek: The Next Generation". I believe most of this footage is from 1988 when the series first began.
Give this a watch, and enjoy some of the character "looks" that might have been, but ultimately, were not. Data had some fascinating possibilities, and Deanna Troi.... her other "looks" were -- well, you'll just have to watch this video to see what I mean. The term 'creative' is a bit of an understatement.