Alpha males dominate in and out of the bedroom, yet still love their woman wholly, and completely. They are protective of their women, with superior looks, intelligence, and love-making skills. They typically hold a position of power: CEO, Duke, Firefighter, Cowboy, or Rockstar.
What woman doesn't want a man in her life to take care of her needs, especially when she's busy with housekeeping, children, a job? She's forever taking care of others, and would love a strong man to help alleviate the burden, taking care of her in her ever-shrinking down-time.
It is probably one of the most popular trope in Romance writing.
And the mis-use of it is probably why non-romance readers hate romance stories.
My aunt: I don't read romance, the heroines are all simpering idiots as soon as the male comes into play.
Well, that's because the male is Alpha, overwhelming her senses and making her do things she doesn't normally do, like relax and let him take care of her (provided there isn't a serious conflict to her doing so).
Unless he's an asshole, then all bets are off.
What is construed as strong Alpha male characters in popular books are frequently men who in real-life, if they displayed these characteristics, they'd be frightening, or arrested.
They follow women around, they force them to eat, they watch them sleep, they dictate what they wear, or how they groom themselves. They have violent temper tantrums when the female tells them no, they force sex, they ignore the female when they're angry.
They're children. And women all over the world love them, shooting these stories into best-seller status over night.
I love a strong alpha lead. Those characters make me feel all warm and fuzzy.
But I hate assholes. They just make me angry.
For me, these Alpha males are difficult to write, because it's easy to write them into asshole status and then I wouldn't be writing characters I love. It's a fine line that's too easy to cross. I've written a couple of men that I feel could fit into the alpha trope, but for the most part, my males are sweet, beta boys, with some alpha tendencies.
Maybe because that's how I like my men in real life?