There is a saying,the train already gone that people say about a missed opportunity..why train?

Question

the train is i meant

Answer 1

"That train has already left the station" I believe is the addage.

No particular reason, here.  It could just as easily been, "The bus has left the depot" or "The horse has left the barn."

However you say it, it means you're too late....

Answer 2

Probably, when that phrase came out, the train was something people commonly missed, thus using the "train" as a metaphor for opportunity.  The same for "That ship has sailed."

Answer 3

Many of our proverbs came from our agraian past, such as "make hay while the sun shines."  Up until the 1940s the train was about your only real choice for long distance transportation, so everyone was familiar with trains and missing them.

Kent in SD