Familiarity, Contempt
If youve been flying for very long, its likely theres a route you frequently use. It could be a quick out-and-back to the nearest $100 hamburger or cheapest avgas, or an hours-long trek to Grandmas house. Its something youve flown often and know well enough to almost do it without a chart. You understand the topography along the way, where the bolt holes are and how any weather may influence the flight. You may even have a couple of the frequencies memorized, along with expected ATC routings.