Q: What's the most common error in social media ads you see?
A: A misunderstanding of marketing itself.
There are quirks and tricks and rules peculiar to Facebook, but at the core of it you gotta understand marketing and have some idea of the customer journey.
Think hard about your customers and how they came to the point of needing your service/product and then tap into that.
People don't want your service because they saw your ad saying how amazing your service is.
There are steps that the customer is going through that is putting them in a situation where they may need you and your service.
What are those 'steps'?
Instead of an ad that starts with "Social Media Marketing For Small Business", I could start with..
"Nothing has gone up on your business' Facebook page for weeks. It's a graveyard. There are digital tumbleweeds. You just don't have the time, you're trying to run a business for gods sake..."