Many developers and designers forget that despite the advanced technologies and the amazing evolution of the web, there are still some users that do not have a strong and stable internet connection. A good example of this is seen if you have ever played internet poker and noticed how many delays there are because other players keep losing their internet connection. There are still users that have small monitors and dial-up modems. Not everyone has a Mac Pro Quad-Core Intel Xeon “Nehalem” processor with a 30” monitor.
One final point – search engine spiders have extreme difficulty trying to pick up content when AJAX is trying to load large amounts of text. Hence, the content isn’t published and indexed properly. Spiders need static content to be able to read it.
Ajax developers at times might need to develop almost two types of applications if they want to build an online application good for Firefox and Internet Explorer browsers that could require a lot more time for application development. The end result however, is well worth it. A highly efficient Ajax based application does not only provide eye catching features but could easily provide a highly effective application with processing speed that almost rivals any simple web-based application.