Once upon a time I answered a question on LinuxQuestions, a slow, ugly website that uses vBulletin--your average, run-of-the-mill, commercial, PHP-based forum software. I couldn't just answer the question, I had to create an account, and give them an email address. Without warning, they started sending me weekly emails, reminding me how awesome they are, what's "happening" with the site and why I should return. Well, I've never been back to the site. There are a few reasons why I haven't been back to the site.

1. It's ugly.
2. It requires me to remember a password, or go through the hassle of resetting the password through email verification.
3. I don't like to hang out on forums. Or, at least, I don't anymore.
4. I actively avoid the site's links when they show up in search results.

vBulletin is bad. It powers a lot of forums in the world, and you can recognize it a mile away. I looked up vBulletin. Amazingly, people pay money for it. I could enumerate its sins for a long time, but I need to focus on one. In order to not receive weekly emails, you have to change your account settings. To change your account settings, you have to log into your account. If, like me, you don't remember passwords for sites you rarely visit, you have to reset the password through email. This is a familiar song and dance to many, but it angers me immensely. It is trivially easy to generate a single, safe, instant unsubscribe link for mailing list emails. Why don't LinuxQuestions emails have a one-click unsubscribe? Easy, they are idiots. They are stupid for using crappy, commercial forum software. They are idiots for spamming my inbox and forcing me to jump through a bunch of hoops to unsubscribe.

Sites like Stack Overflow use my OpenID login, which I know well. I can remember a single username / password for multiple sites without the fear of one site secretly stealing my password and using it to log in to another site as me. Trust me, more sites than you want to know store your password as plain text in their databases. Why am I picking on this one website? They are trying to get more visitors who provide more content, so they can extract advertising money or satisfaction that they are helping Linux users everywhere. They want to be a popular destination for a certain niche, but they completely fail to create a compelling experience in any way at all. It is so bad, I actively ignore search hits for their site.

Software matters. Usability matters. You can't just punt on the software. Invest in it. Pay a real designer and get a real programmer on your team. Unless you are independently wealthy, you need a software developer on your team. This software developer will want to make the site awesome, since he is personally invested in the success of the site. People want to know what makes a website successful. Ultimately, its the folks writing the code who make or break a site. The software developer needs access to the code, so don't even dream of buying a closed-source, commercial solution. Start with the best open source solution (let the software developer pick), pay for a good design (don't do a design competition, that's exploitative), and let the software developer merge the two. Your software developer uses social web software all the time. He knows what's good. Force him to eat his own dogfood (use the site himself), and he'll work harder at improving the experience. Elicit feedback from your users and implement popular features.

The tragedy is that these old, broken forums end up loaded with useful information donated by the users despite the shortcomings of the software the site rests on. Don't post useful information on these sites. Please, don't encourage them.