So, what makes a good recommendation?

1. First-person experience.
2. Enthusiasm.
3. Specificity.
4. Sincerity.
5. Clarity.

The difference between good (action-inducing) and bad (zzzzzz) recommendation is the difference between one person saying:

“I'’ve read a lot of history books, but this is the best I’ve ever found on the Roman Empire, and if you read it you will have a firm grasp on Roman history and architecture and I guarantee you’ll be booking the next flight to Italy.”

and the other saying,

“I guess I liked this novel, but you probably won’t.”

Which book would you buy?