You ask, “how do you determine that they're too unlikeable?”

Just in general? Here are some questions to ask:

• How will my readers feel about this character?
• Is that how I want my readers to feel about this character?
• Does this character fit the tone of my story?
• Is any of the content going to be a problem for my audience?
• Would a more-sympathetic villain be more interesting?
• Would another kind of villain help develop the themes of the story?
• How many words or how much time would I need to flesh out this character more, and what else could I do with it instead?

One example that jumps to mind is a Fantasy novelist who decided she wanted to explore why women like one of her protagonists stay with a certain kind of boyfriend, and give her readers a warning about them. And that only works if the reader understands what she saw in him.

You ask, “how do you determine that they're too unlikeable?”

Just in general? Here are some questions to ask:

• How will my readers feel about this character?
• Is that how I want my readers to feel about this character?
• Does this character fit the tone of my story?
• Is any of the content going to be a problem for my audience?
• Would a more-sympathetic villain be more interesting?
• Do the other characters react appropriately to what the villain has done?
• Would another kind of villain help develop the themes of the story?
• How many words or how much time would I need to flesh out this character more, and what else could I do with it instead?

One example that jumps to mind is a Fantasy novelist who decided she wanted to explore why women like one of her protagonists stay with a certain kind of boyfriend, and give her readers a warning about them. And that only works if the reader understands what she saw in him.

You ask, “how do you determine that they're too unlikeable?”

Just in general? Here are some questions you could ask:

• How will my readers feel about this character?
• Is that how I want my readers to feel about this character?
• Does this character fit the tone of my story?
• Is any of the content going to be a problem for my audience?
• Would a more-sympathetic villain be more interesting?
• Would another kind of villain help develop the themes of the story?
• How many words or how much time would I need to flesh out this character more, and what else could I do with it instead?

You ask, “how do you determine that they're too unlikeable?”

Just in general? Here are some questions to ask:

• How will my readers feel about this character?
• Is that how I want my readers to feel about this character?
• Does this character fit the tone of my story?
• Is any of the content going to be a problem for my audience?
• Would a more-sympathetic villain be more interesting?
• Would another kind of villain help develop the themes of the story?
• How many words or how much time would I need to flesh out this character more, and what else could I do with it instead?

One example that jumps to mind is a Fantasy novelist who decided she wanted to explore why women like one of her protagonists stay with a certain kind of boyfriend, and give her readers a warning about them. And that only works if the reader understands what she saw in him.