You go for a looks-like prototype when you have a team and want to inspire them to move forward, when you want to impress investors or when you are planning a K

You go for a looks-like prototype when you have a team and want to inspire them to move forward, when you want to impress investors or when you are planning a Kickstarter or similar. You go for a works-like prototype when you're experimenting with concepts or want to try out something new. You're completely correct in your assessment.