Start your text with a question or a problem. There are 2 ways to start your text in image ads - a question with an answer or a problem with a solution.
Why it's recommended to start with a question? When we see a question, it's physiologically impossible for us not to answer this question. It concerns silent answers too.
Why it's recommended to start with a problem and then offer a solution? The reason is that no one buys products, all of us we buy a solution. Women never buy dresses, they buy their attractive looks and the feeling of looking good. The same way men don't buy drills, they buy holes.
There is a term called "interaction marketing" which works well in social media when the people scroll down their feed line. In case your question is short, it has more chances to attract the attention of your audience.
For instance, Do you love skulls?