The main issue is people who are long time members aren't voting ... for anything. We've been seeing this issue on Mechanics.SE for a long time. Recently a few things have changed which brought on more voting. The main thing over there is, Jon Ericson brought it to our attention we are getting poised to become a real site, but we don't have enough of a middle class to have a decent election.
DIY.SE is a lot like Mechanics.SE in a very pertinent respect. Unlike the programming or IT sites on SE, there are a lot of users who come onto the site looking for one time help. They have no intent of sticking around after they get an answer (and sometimes don't stick around to get an answer). They post their question, get their answer, and leave. This mainly happens for two reasons: 1) there is no incentive to stay; 2) they have no investment in the site. You cannot expect these people to vote on your answers ... ever. Who will vote on those answers then? The only ones who will are those who have been here and continue to come back.
What does that leave you with? It means that those who are here regularly need to vote, which it appears is not happening. Everyone can place up to 40 votes in a single day. Every users here has had the ability since the beginning of the year to vote up to 1520 times, yet the highest voter on the site only has 323 votes on the year. That is only utilizing 21.25% of their voting potential ... and that's the highest voting individual!!
In order to change what's happening on DIY, everyone needs to take the initiative and start voting. Don't act like a vote for someone else's post is going to cause you harm, because it's not. Are you so stringent in what you think is a good answer that you don't need to vote at all?
I personally use a guide to voting something to the effect of:
- Upvote an answer or question if it has some redeeming value - Does it add value to the site?
- Leave a question or answer alone if it doesn't bring anything or it may have some moderate issues.
- Downvote a question or answer if it is so egregious it shouldn't even be entertained.
To emphasize my point ... on Mechanics.SE I have recorded 5,406 votes, with only 22 of those being down.
The issue being described is systemic. You cannot blame those who only come to get their questions answered, though you can remind them to upvote and check the answer as being just that. You may be able get some of them to stick around, but right now you aren't giving them any incentive to do so. By making an effort to reward people for their hard efforts, whether it's a question or an answer, you give them incentive to stick around and become a productive member of the DIY.SE society. Give people a reason to stay. Give them a reason to vote. Give them a reason to enjoy.
Jon Ericson left us one other tidbit. He showed us this post which I believe says a lot about the subject:
Vote Early; Vote Often
There is also Jeff Atwood's take on the subject:
Vote Early; Vote Often
Another person from Mechanics.SE left this post over on Gardening.SE which seems to be having the same issue as DIY. His review of the situation there could shed light on what's going on here. It is well written and a good read
I wish DIY all the luck in the world. You have less to worry about than does Mechanics.SE because you are a graduated site. Hopefully it will all work out in the end.