Q. What is framework?
Ans. 

According to hypeframework

hypeFramework is a collection of scripts, views and cascade style sheets that create an enhanced framework within Elgg. hypeFramework allows to avoid repetitive functions and snippets of code. Generic scripts contained with hypeFramework are recycled throughout hypeJunction plugins.

According to phloor:

Enables the core phloor environment. It provides basic functionalities, classes and views for all current and future phloor plugins.

So i think it is clear by the definitions why developers develop framework, of course to make their work easy! lol and save your bandwidth!

Why many of you afraid from frameworks?
Ans.
It’s clear that your are brain washed. if you found any problem in any framework than post the problem to plugin page instead of creating a new discussion topics.