For me a lot has to do with setting and impulse. I‘ll take a week off from work and lock myself into a hotel with a spa. The weeks before I spend curating a learning/reading list (which is mostly a reading list plus a definition of the sessions goals) and hesitate to read any of it early on. This keeps up a certain tension while collecting material (after a couple of days most people me included tend to start looking for new adventures otherwise). However I <i>passively</i> start to think about the topic and every time something new comes to my attention it’s sorted to the list.