You have a territory list and a sequence ready. Before you send it, you check the account: a search of the news, the last earnings call, the careers page, maybe a permit lookup if you know the county. An expansion turns up as a press release, a remark on a call or a trade-press story.
That is the same day every other vendor selling into that plant hears about it, and by then the pad is poured and the general contractor has picked the subs. The plant that broke ground last quarter sits on your list with no note on it.