Notes from Y Combinator's How to Start a Startup 1

I just want to take this class as a soft skill for future. I might need them, who knows? So I will starting to take note for any valuable idea that I saw during the class. Here is the link for the class. This is a series article I will keep updating until I finish the class. Thanks for anyone who is reading it. If you have any thoughts or ideas. Leave a comment.
Today I read an article that talked about how a person found a cleaning company from his life experience. The company is called Homejoy, founded by Adora. Adora is a lazy person who doesn't like to clean his/her room. However, s/he find out that the cleaning service in San Francisco is very inefficient. Thus s/he begin to do some research and advertising his/her company.

Solve problem systematically

I just read this article that talks about how an entrepreneur use systems to massively increase their recruitment process. Simply by asking a systems of questions. Showing below:

1. Why do we color-code microfiber cloths?
2. You can spray all-purpose cleaner directly on electronic equipment. True or False?
3. You should mop before you sweep or vacuum. True or False?
4. If a client is not home, it’s okay to use a client’s supplies without their permission. True or False?
5. It is unprofessional to take personal calls while working at a client’s home. True or False?
6. You are at a client’s home and you see a $20 bill on the table. There is no note or message on the table indicating what it is for. There is a wallet on the table. What do you do?
7. You see a pile of unfolded clothes on the floor in your client’s bedroom. What do you do?

These questions seems pretty stupid and it does not guarantee a qualified worker. It still make Homejoy (the name the company founded by author) light years ahead, why? I think it filtered out people who is not serious about this job. It also give an impression to the applicants how they should behave under certain circumstances.
More importantly, do your research and execute is most essential part of starting a startup.