MLS makes an interesting point. Does a person's attitude to one thing reflect their attitude to everything? The answer is probably yes, but it needs to be looked at more deeply than he is doing (or implying in this thread anyway).
To take my logbook as an example (only because I know about me), it isn't actually very scruffy. But it isn't completely neat and tidy either, mainly because I carry it with me, fill it out as I go, change things if necessary, and don't worry too much so long as it's reasonably legible. As I see it, I take pride in it being readable, but appropriate.
Now, does this reflect the way I do other things? Yes, actually. If you ask me to do anything, from writing an article to sending you something in the post to arriving at an airfield, I'll do it immediately and well. But I won't worry too much if it doesn't look perfect, if looks are not the primary consideration. And I am a careful pilot, but I don't insist on care for it's own sake, only when and where I feel it's required...which means, for instance, that I occasionally forget to fasten waist harnesses in an aircraft when it's on the ground and I'm about to go flying again in half an hour.
Now, let's take the friend I mentioned. This person keeps a very neat logbook at home, but it's always several months behind.
If asked to do something, this person will do it perfectly, but that quest for perfection means it may take ages and ages for it to be done, even if time is important and looks aren't.
I'm sure there are all sorts of variations on this theme, and they probably all tell you something about the person concerned. The trouble is, without knowing ALL the facts, and the reasons behind them, it's not always completely clear what the conclusions are.