Why Jump a Job?

I've been working since 2006 and I guess i qualify for this question as much as you all, not pretty sure if I could justify my statements but these are the facts attached especially in Indian companies:

1. Better Salary package: Okay so my first and foremost question is if another company can hire an employee with a better package what stopped the current org from paying him / her an equal proposition? The fact being the hiring process remains the same for all companies mostly so you end paying for another candidate what your current employee can perform with. I still can't find an answer to it.
2. Designation Change: If an employee deserves to be a role higher than what he is doing in another company who is the loser here, the employer or the one who is employed? Thinking over the terms I guess the org is losing it's value by defaming any employee who has worked with them.
3. Other reasons being egos, non-reliable, process shutdown, internal politics.... you can keep adding the reasons, so being worked with 7 companies I can assure you sometimes we shift because we are not treated good, false promises and more. Let's keep it clean and straight on the face. You wish to fire or hire an employee I guess writing a feedback on them with a decent note reasoning their decision would be an awesome way to conclude these misunderstandings.

These are just a few which came o my mind, why don't you throw some insights from your experiences?

Wini.