The summary is where you quickly tell people what you can do for them, not where you tell the world how great you are by listing all your accomplishments.
Nobody cares about your accomplishments.
All people care about is finding out as quickly as possible what you can do for them. This is what the summary block in your profile is for. Tell your viewers right off the bat what it is you offer and how you can help them solve their problem.
Think about it: On LinkedIn, Google, or anywhere else, when someone searches, they're looking for the answer to a problem they have. People search because they have a need for something.
That need creates a problem that you have the opportunity to solve. Present your solution immediately and succinctly in the summary section of your profile and you'll stand head and shoulders above those who use the summary block to write their autobiography / personal brag sheet.
If you need help writing a business plan, are you interested in sifting through a summary that lists all kinds of self-promotional trivia and trying to discern from it if this person is able and willing to help you write a business plan?
Or would you more readily engage the person who writes I CAN HELP YOU WRITE YOUR BUSINESS PLAN right at the top of their summary?
The same applies when people are searching for someone who does whatever it is that you do. The person who most quickly and succinctly presents a solution to the searcher's problem is far more likely to be engaged than the people who think the summary block is all about them.
Remember, everything in your profile must be client-facing. It's not about you, it's about what problems you can solve for someone else. Write for your audience and not for yourself and make sure you keyword appropriately.
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