When people talk about ECMA they aren't discussing a personal hygiene problem or skin disease, but a scripting language standard. In such a system, useful functionality is already available through a user interface, and the scripting language is a mechanism for exposing that functionality to program control. Scriptable applications allow scripters to directly manipulate a program and its data files, unlike macros, which merely mimic user actions. Scripting lets you link components.
Scripts take much less time to write than system code.
The programmer must do less housecleaning as the script platform handles most of the tedious memory and data problems. The script environment protects against programming bugs. All calls in a script environment must pass through the script environment, which can then impose any level of security on the code. Most script languages offer a security model with a huge variety of security options. Easier to debug.