Chaos Space Marines Assembly Line
It takes rather long time to prepare and assemble full model, especially when you try to make it good one. When some interesting idea comes into your mind it takes you few minutes to clean legs, minute to glue it onto base, minute to glue body, minute to search for hands/head/shoulders, another 5 minutes to clean those parts, and another minute to clean glued body. So about 15 already wasted, your awesome idea had a good chance to flee away.
Finally I found solution that works for me. I am preparing the most usable parts long before idea comes. Chaos Space Marines have 4 types of legs and 8 or 9 types of bodies. It is possible to prepare 12 legs, glue 12 bodies and put everything on the shelf. Now you can start modeling almost instantly, and it saves a lot of fun because boring process of cleaning legs and putting body together does not distracts you from the main idea.