If we want to create protagonists that are worthy of telling our stories, we need to dedicate the time to develop them as people. Crime, chick lit, horror, fantasy - whatever the genre the rules are the same. It's our job to create characters that readers are going to care about, but in order to do that they have to be realistic, memorable and ultimately they have to be human.
Sometimes writers can get so caught up in the idea that their protagonist has to be likeable that the character often ends up bland and uninteresting as a result. There's nothing worse in my opinion than a invulnerable, uninteresting protagonist who never slips up and always does the right thing.
When writing we need to ignore the little voice that constantly warns us of decreasing our protagonists likeability. Imagine your protagonist asb a lump of clay in need of being shaped and turned into a finished product. Use your characters flaws against them, have their fears or mistakes stand in the way of getting what they want. It makes for a much more interesting character arc, adds inner conflict and ultimately that character growth will drive your story as much as your plot.
What I am saying here is that character likeability has nothing to do with perfection. Film, television and literatures best loved characters are the ones that battle with inner conflicts because it makes them human, it makes them realistic. If you're readers can relate to your protagonist, they will root for them to overcome their problems, which will give your story a much more satisfying conclusion.