Every time this comes up someone says "concentrate" and someone else says "20 to 30 names" and someone else says "if you can't follow them all, hold fewer." I get it, but none of it answers the actual question. I want to know if there's a real framework for deciding how many individual names a retail investor with a full-time job should actually carry alongside an index core, not just receive wisdom or "whatever feels right." Has anyone arrived at a real number through reasoning or did everyone get there by accumulating names one by one and then trying to justify it?