For a very esoteric reason, actually.  Companies usually offer dreadful tech support of their products.  Between the call-around, rude CSRs, and unclear billing practices, it’s much easier for the tech-savvy just to search the web for solutions.  Between my personal and office machines, I’ve got four desktops, one Tablet PC, two random boxes, five virtualized machines, and a smartphone.  Mac OS X (BSD), Linux, Windows Mobile, and up to four version of Windows NT (5.1, 5.2, 6.0, and 6.1 — that’s XP, 2003, Vista, and 2008).

I run into edge conditions and conflicts all the time.  Happily, I can usually pick the search terms right and find the solution within the top 10 search hits.  But sometimes, it takes a whole runaround: maybe the author used different terms, or the terms are ambiguous and clutter up the search results with unrelated problems.  Sometimes, I strike out on searching and end up investigating personally.

As long as I’ve already wasted the time, I might as well describe it and save someone else the time.  Even if I end up finding a solution on someone else’s blog or forum posting, adding another link could boost that page’s rank, and adding my own phrasing might cause a like-minded person to stumble on my post.

I could just add pages to my web site, but a blog reduces the activation energy.  Of course, anything is fair game now that I’ve got it set up…