Part of making a successful product is making it usable for your target audience. That, apparently, is something that Amazon completely missed with its new Kindle Fire.

“Amazon.com’s new Kindle Fire offers a disappointingly poor user experience,” said usability expert Jakob Nielsen in his report. “Using the web with the Silk browser is clunky and error-prone. Reading downloaded magazines is not much better.

It’s no surprise that one of the main observations in the study is that everything was just too small. Repeatedly tapping on the screen and never quite getting to where you want to go.

“You haven’t seen the fat-finger problem in its full glory until you’ve watched users struggle to touch things on the Fire,” said Nielsen.”

Being able to navigate the Kindle Fire’s small screen isn’t the only problem. It’s also a heavy beast. According to Nielsen, the Fire is “unpleasant to hold for extended periods of time. Unless you have forearm muscles like Popeye, you can’t comfortably sit and read an engaging novel all evening.”

That’s not good for a device that’s actually meant to be used to sit and read for an evening.

While they do serve different markets, the iPad’s design is sleek, light and its 10-inch screen allows users to easily navigate full Web sites. Apple’s device also gives users lots of power and the ability to run complex apps and games.

Like most other companies entering the tablet market, Amazon has a long way to go.