When to reach out to potential investors?

Hey folks, I'm evaluating a handful of promising businesses and would like feedback on when it's appropriate to start reaching out to investors for a soft commitment.

My initial thoughts were as soon as an LOI has been accepted. I'd like to reach out ahead of time to introduce myself, but I've also heard investors can't entertain every searcher that reaches out, so having an LOI accepted shows you're serious. Any thoughts on best practices here?