What is the point of the cabinet position "Leader of the House of Commons"?

Question

This position was traditionally held by the PM himself, and there was only a Leader of the House of Commons appointed at times when the PM was not a Member of Parliament - eg Lord Liverpool and Duke of Wellington held the PM job (First Lord of the Treasury) while not being elected MPs, they were in the House of Lords.

Why do we need a Leader of the House when the PM has a seat in the Commons?

Answer 1

No point at all, ministers love to create jobs for themselves, and after all, who are we to stop their snouts gorging in the public trough?

Answer 2

This position combines the roles of delegate, manager and representative. The job involve managing the House's legislative programme, representing the government on the House of Commons Commission and representing the House in cabinet. She will lead on debate involving items dealt with by the House of Commons Commission such as MPs remuneration and expenses and House procedure and process.

The current incumbent is the RT HON Harriet Harman QC MP who also has responsibility for equality and lead on women's issues.

Answer 3

It is now commonly used as a minister without a portfolio position.  Going back into the last couple centuries, the holder of this office commonly did the PM's job of supervising Parliament on a day-to-day basis, allowing the PM to focus on more executive type duties.