From time to time, while designing new web-sites, I am asked to consider fly-out menus (sometimes called drop down or roll over menus). In most cases, I steer my clients to more user-friendly, more efficient solutions; but in the process, I end up repeating the same basic points many times. So I decided to post my thoughts on fly out menus here and refer people to this entry.

First, let me go over the benefits of fly out menus. They are attractive, some might even say cool. They can save a lot of space.

Despite this, in most cases, the negatives far outweigh the positives. Here they are:

1. Fly out menus can hide important information

With fly out menus, you can't see all your options at a single glance. While this may not seem like such a big deal, it is. One of the single most important things about a well designed web site is that Users need to know where they want to go at first glance, immediately, pronto - you get the idea.

How can you do that if your site actually has a lot of options? Get to know your Users. Know why they visit your site, know their navigational patterns - this will help you arrange the content along the paths they take. In most cases, it will allow you to actually reduce the amount of initial choices Users have and make it easier for them to navigate the site.

2. Fly out menus can fly out at the User

Even worse, sometimes Users think they know where they want to go, they move their mouse to the appropriate button, and then a bunch of new options pop up. This phenomenon slows Users down, at best, and at worst, disorients and distracts them. There's nothing worst than being presented with more options when you've already made your decision.

3. Fly out menus reduce your ranking in search engines and block people who use assistive technology

Fly out menus use JavaScript. Links which are hidden in JavaScript cannot be followed by Search Engine Spiders and screen readers. In simple terms, this means that you reduce your ranking in search engines by using fly out menus.

All this doesn't mean that there is never a case in which fly out menus are merited. Each case is unique and the positives and negatives always need to be weighed. But for most web sites, you want to let the idea of fly out menus fly away.