For me, this is the most surprising missed opportunity:
"posting original stuff to groups with thousands of members and not receiving a single comment or click to some link"
LinkedIn had the chance to build some amazing forums. LinkedIn should be the place that you think about when you want to have a conversation about business. They clearly have the traffic. They could have done something amazing with their groups and discussions. They have wasted all of their chances.
Every time they touch Groups, they make them that much worse.
They made a big (incomplete) UI overhaul which managed to make them less easy to use, and half the time fails to load posts (every 1-2 posts as you scroll down is loaded via script, fails a surprising amount of the time, or simply refuses to fire!).
I'm at a total loss as to why they hate Groups so much. Not enough page loads / ad impressions? We run a few groups - ranging from 10L to 90K in size, some of which are quite active. But discussions tend to engage ~.001% of users.
From my perspective, discussion groups at linkedIn fails to deliver because 99% of posts in the groups are shameless self-promotion. Posters and group creators are not seeking knowledge or discussion, but wish to promote their own new product, company. The same goes for nearly all posts on linkedin: the site is treated as an advertising channel by all involved.
"posting original stuff to groups with thousands of members and not receiving a single comment or click to some link"
LinkedIn had the chance to build some amazing forums. LinkedIn should be the place that you think about when you want to have a conversation about business. They clearly have the traffic. They could have done something amazing with their groups and discussions. They have wasted all of their chances.