An immutable law of the universe, the 10-5-3-1 rule.
If you are running a process for anything, you need to start with 10 options, 5 will respond to a request for proposal, 3 will be real options and you’ll be able to select 1 clear winner.
If you are hiring a general contractor, finding the right school for your kids or picking a flight school you ignore this basic rule at your peril.
Start with fewer than 10 and you may not end up with a viable solution. Start with more and you’re likely to get bogged down and lose momentum.