You have 100 words to sell yourself, and that is something that a lot of people are not comfortable with.
I have that problem, but I did play along. I had a story Idea floating in my head, (they never finish floating around), How to make an autobiography in 100 words, not possible at all, so I started at the beginning, the real beginning, but it wasn't about me so much as it was the story Idea.
A sales pitch is nothing more than a story after all.
People look around at the bigger accounts and try to mimic how they post, expecting to get the same results
It is unfortunate in this day and age, with as long as the internet has been around, and social interaction on line have been around that people still feel they need to parrot/mimic others in the hopes of making it big, instead of being themselves.