Most older lifts have a logbook kept in the machine room, a worn notebook with dates, initials and a line or two for each visit. We ask to read it before an inspection starts, and it often shapes the hour.
A repeated note about the same door tells us where to look first. A gap of several years tells us the checklist should be slower there. Entries are short, and the handwriting changes, but the pattern is usually clear in ten minutes.
After the visit we add our own line to the book, with the date and the report reference, so the next person who opens it finds the thread.