The 5 is even more because it was originally a larger number, but I get lazy/procrastinate and pull a "5 more minutes!" and settle for leaving at 10:25 instead of 10:15 or something. Hell, my first semester at college it was even 10:18 because that's when I could more often than not make the commute in 3 minutes flat as no one else was on the road. I suppose I'm good at justifying exceptions to the rule too.
Heh, yeah, mine is more time based. Most of my things are left in big piles, but I know where everything is. The stuff I used recently is on top, and more distant things on bottom. Makes perfect sense IMO. I also have a thing for only stopping one activity and starting the next if the time is divisible by 5, even if it doesn't matter for any reason. Fortunately, when the need arises, I can just tell myself that it's all just silly, so it doesn't interfere with life too much. I mean, I also do things like discover at what time there will be the least traffic and leave then, etc. I have a thing for finding the most efficient use of time like that.
Yeah, I have an even deeper rooted motivation: OCD. Though my former roomate who's going into psychology tells me it's some other letter soup thing really, as I don't care about neatness, but I do need things mentally organized. The whole "lock the door three times", "let the alarm ring 3 times" thing is mixed in to boot.
I'm very routine oriented. I like plans, though it's mostly habit that guides me. The problem is that if I'm distracted I forget what my routine is, even if I've been doing it for years. I used to always get the same thing at Subway, for instance, but all it took was forgetting one time and now I get stuff that's close, but not quite the same because I can't remember.