Your LinkedIn business headshot is your online business card to connect and engage with your audience and potential clients. Yet as a professional portrait photographer (based in Brighton) I have seen thousands of LinkedIn accounts with:
blank profile picture (this makes you less real in the virtual world)
selfies (this sends a message of not being professional and serious)
blurred low quality portrait image
headshot with very distracting background
very old cropped image from some sort of event or wedding!