Over the years, I’ve dealt with (and worked with) many vendors, as I’m sure you have too.
Some will bend over backwards to help their customers (or potential customers) out, finding workarounds to their own internal rules to help make something good happen.
Others will persuade their customers into signing a contract before bending their customers over backwards, finding internal rules to their own workarounds to make sure nothing good happens.
Which group do you think customers prefer dealing with? The answer’s obviously the first.
But having been the impartial advisor in vendor selection processes, the group the customer prefers dealing with doesn’t always equate with who they sign a contract with. That answer seems less obvious – to me at least (acknowledging though that there are many factors that go into an OSS purchasing decision).