I've been wondering about this lately. Well, not so much why others write theirs, as why I write mine and whether this is sufficient reason. I write it for myself, and if others enjoy it that is the icing on the cake. This sounds a bit perverse, but I read something similar in another blog I can't find again now, so it's not just me!
There are two reasons for this. Presenting an account of what I have done in public helps to motivate me to get something done in the first place. Secondly, I live a rather isolated life and publicising my gardening endeavours changes that a little.
I want only those people to read it who actually care about it, so I deliberately try to resist prettification and tricks that might make it more appealing. On the other hand, I hate to think that people might comment because they feel sorry for me, if for example there are no other comments to a particular post: I want them to comment because they had something to say, just as I do. And yet I want reading my blog to be enjoyable for the ones who put a little effort in, so quite often I sneak my nicer pictures in a little further down a posting, as a reward! At other times I weaken and feel more attention-seeking, and I pick a tricksy title (ahem, like this one) and some eye-candy (of a strictly horticultural kind, usually) to start off with.
Originally I didn't intend to blog every day. In fact the plan was quite specific and different, and the blog's URL gives it away. I have an old gardening book, from the 1930s although my edition is 50s, which sets out tasks for the garden on a weekly basis (with further sections on what to do generally over a month too). I wanted to try to keep to it for a year and I thought this would make a good, structured blog. But when I began on the garden it quickly became clear that it needed so much remedial work that there would be no time or energy left to get round to the tasks specified. Now, it seems that perhaps I will manage it some time in the next few weeks, which is very exciting to me! I will say more about the book when that time comes.
But I wonder why other people blog, and what they get out of it, and whether they get in quite as many existential tangles over it as I do?