Golden Rules of Communication- 20 Trust Building Tips in the Age of Distraction 

14. Do not use the very impersonal default message on LinkedIn when sending an invitation: “I’d like to add you to my professional network on LinkedIn.”  How much additional time does it take to write a brief personal note?

Full article:  https://www.noreenkelly.com/2015/02/golden-rules-communication-20-trust-building-tips-2/