1
general::
1. Fail to take advantage of an opportunity, as in Jean missed the boat on that club membership. This expression, which alludes to not being in time to catch a boat, has been applied more widely since the 1920s. 2. Fail to understand something, as in I'm afraid our legislator missed the boat on that amendment to the bill. [Mid-1900s] Also see MISS THE POINT.
American Heritage Idioms
2
general::
Phrase(s): miss the boat
1. Lit. to miss out (on something); to be ignorant (of something). • Pay attention, John, or you’ll miss the boat and not learn algebra. • Tom really missed the boat when it came to making friends. 2. Fig. to have made an error; to be wrong. • If you think you can do that, you have just missed the boat. • The guy’s missed the boat. He’s a lunkhead.
McGrawhill's American Idioms And Phrasal Verbs