Why do I fail to impress at interviews?

I would say I'm pretty smart.  Friends tell me I'm very smart.  I'm also logical and fairly rational.

So why do I fail so miserably at convincing employers that they should hire me?  They like me.  But they don't hire me.

Part of the problem is the tech industry.  There are a multitude of programming languages and methodologies.  New ones are created often and older ones go out of style.

So having the latest and greatest skill set can be a challenge.

The currently sought after skills are all web-based.  It's hard to have web programming experience when you've spent the last ten years doing database and Windows programming.

I've used at least 4 different programming languages and 5 different scripting languages.  I can learn new languages.  Easily.

But everyone says that.  So how do I convince the interviewer that I really mean it?  My references will confirm it, if I can convince the interviewer to call.

Anyone need a T-SQL, C# programmer?

Sigh.