Why don't you write faster?

I’m actually considered a fairly prolific writer. I’ve been writing for 2 houses (Harlequin and St Martin’s for several years, as well as doing novellas for both them and other houses.) Some people write faster than I do, some slower. Each writer can only write at their own speed and as fast as they “get” the ideas from wherever it is those ideas come from. I don’t like to think about where my writing comes from because I’m afraid if I analyze it too much, it’ll stop coming!