Scripting was made easier for web-content designers who have little or practically no knowledge of the core Java Language.
With EL the web-content designer needs only to know how to make proper calls to core Java methods.
The most obvious limitations were that its expressions were evaluated immediately, and the JSF components could not invoke methods on server-side objects.
Version 3.0 of the expression language (the unified was no longer deemed necessary) was developed in a JSR independent of the JSP and JSF specifications in JSR-341.
[3] Removal of a long deprecated method, clarified ambiguities in the specification, added small usability enhancements.