Personal feedback is generally useless, we need a trigger to change.

Great article by Mark Suster:

http://www.bothsidesofthetable.com/2011/12/07/why-id-rather-err-on-the-side-of-direct-feedback-than-pleasantries/?utm_medium=bothsid.es-facebook-share&awesm=bothsid.es_q3D&utm_source=facebook.com&utm_content=awesm-publisher&utm_campaign=

My personal view is that feedback is good if it is directed at an object (presentation, company, pitch) but almost always useless if it directed at a person (you should to be more understanding, you should not be so lazy etc). Unless the person is willing to receive it, you can try all you want, the other person might even nod in agreement but it will be forgotten. People need a strong trigger to change and feedback is a lousy trigger.

Practical application:

I wanted my co-founder to be more structured about certain things.. I have stopped telling, and started creating structures myself to force him to be structured around it. 

In a sense it is like building a business. People dont change until they have to. You need to prod at / create a pain point for people to care. 

To quote a Mr Sheldon Cooper,

"Change is never fine. They say it is, but it's not!"