Its difficult to claim perfection in anything, even Ajax. While Ajax has enhanced the web experience for many users, and there is not shortage of people constantly praising its merits, it is perhaps no longer the newest standard. Sure, it allows relatively easy integration of interactive elements in web pages, but is it really all that powerful and versatile as is often claimed?
There are three major standards for the development of Rich Internet Applications: Ajax, Java, and Flash. None of these are perfect solutions, but each has its own advantages over the others.
This is where the choice comes in. Ajax is at its strongest for such applications as information submission, but weaker when applied as a true asynchronus system.
On the other hand, Ajax is probably the most versatile of the options available. While not always the most efficient, it can get the job done. Many of its disadvantages can be blamed on web browsers not following standards and not being optimized for the desired degree of interactivity.