The problem nowadays is social media. Companies/designers want to hire models with the biggest social media followings to bring attention to their brand. Someone like Kendall could bring a company millions of new customers while your average girl on the street could not. It's no longer about who has the best "look" or who is the best model, it's all about who is the most popular and who can attract the most $$ for the company. I think we can all agree that Kendall isn't the best model and would be a nobody without her name and connections, even all the other ones(gigi, bella, cara) all have rich families and connections that gave them a career. None of those girls would be famous models if it weren't for the families, but unfortunately that's how the world works.