What's the biggest mistake people make on Reddit?

I think the most common mistake people make is viewing Reddit as another marketing channel. Many jump in, start dropping links or advertising their services without establishing any credibility. The reddit community can smell self-promotion from a mile away.

The most successful accounts are usually the ones that take time to engage in discussions, learn the culture of the subreddit they are posting on, and establish themselves as someone valuable before posting anything promotional. Once they trust your account, you can post promotions with ease.

The most effective method is, in my opinion, engagement and consistency, not aggressive promotion.