What do you look for in a witness?

What attributes/actions most influence your voting?

With an ever growing list of witnesses to choose from, one's job of voting will become more involved. For witnesses, it is easy to imagine that individual feedback may come less frequently as users split their time more and more. Also opinions can differ from user to user, so hopefully this can capture the spectrum of opinions of the community and potentially highlight the most popular ones. From the perspective of both a user looking to compare their options and a witness interested in improving the services offered, I thought it might be interesting to discuss desired witness attributes or actions in a more general way.

So, what do you look for in a witness?