The reflection was precisely in this context: What if a culture was created within the community in which people sell more than they invest in the community?
Some people do (see the comment I left for @brainylady), and it doesn't go unnoticed. It's all about how you want to be viewed here in the community, and that has to come from you, no one can tell you how to manage yourself.
You've got nothing to worry about, it sounds like you aren't here to milk the system and are looking to be part of the community in a genuine way. If you need any help or want to ask any questions feel free to send me a comment anytime.
My comment about "milking the system" is generally directed at those who take and give very little back. It's usually further backed with disingenuous engagement and spam.
RE: When is the best time to withdraw POB? A sincere doubt not to harm the community.