Some people may just ignore you if you are still labeled a "Newbie." That, or they just outright not believe you, since people seem to be cautious of any newbie account being an alt of someone else... I'm really kind of shocked to see all of the threads in the Services sub-section with people selling accounts (I assume to get buyers to participate in sig campaigns faster), and selling trust scams, etc.
I guess if the forum allows alt accounts (which I thought it didn't, btw), and encourages signature campaigns that relate to how much activity an account has, it leads to this. I like the activity versus post count as mattering when choosing what level someone is, but it still has the downfall of people posting just to post, versus actually having something to say. I would think being a member for a longer period of time should have more sway as to activity too, because it means you stuck around and know how the forum works.
I'm probably one of the few "Newbies" who actually read the Meta about post count, activities, and trust, to get a feel for the forum before jumping in. But I've already been ignored as if I wasn't even there by someone, and that I have to assume was based on my low post count/Newbie status at the time, since everyone else who was posted to, had a lot more posts then I did. (the thread I'm discussing: https://bitcointalksearch.org/topic/need-web-research-done-1-btc-849522)
This. Obviously, people can't make a career off of signature campaigns, but it's a nice way to earn a little extra cash