Its a bit more nuanced than that. The ones I have seen, that unless a Bryant, Chapman, JD or some clear upgrade like that is available, there is no point in paying someone marginally better, but to use Espinal/Biggio/Smith initially and bet on Moreno being the real deal. And put that money elsewhere.
It's about optimizing return on investment.
Also, wrt Kikuchi, if he turned down $13M from the Mariners, that doesn't necessarily mean he will turn down $13M from the Jays. Sometimes a player wants a change or doesn't like the org.