Inside Higher Ed has summarized some findings of a study by Carnegie Mellon University anthropologist Lauren Herckis about why faculty hesitate to try new teaching practices. (The article in IHE uses the word "innovative," but I find that word loaded, and since I don't know if or how it was used in the study itself, I'm going to avoid it for now.) The one that made the headline of the article is faculty being afraid of looking stupid in front of their students, but two other important ones were fear of punishment from bad course evaluations (or "smile sheets," as they are sometimes derogatorily called) and deep "gut" convictions based on personal experience that they know what good teaching is and will prefer that instinct over the findings of a research article. Read the comment thread as well as the article; the discussion is fascinating (and tends to back up the latter two findings).
We happened to interview Dr. Herckis for e-Literate TV a while back, and here she is making a related observation:
I also recommend reading John Warner's response in IHE about the necessity of being comfortable looking stupid. Great stuff.
A couple of commenters on the original IHE article asked for a link to the original study. I don't have one at the moment and am not sure it's been published yet but will post it when it becomes available.