It goes back to what is most likely to happen.
Let's say you've got four options:
He's awful from the jump and completely useless.
He's decent but never cements a consistent place either through form or injury.
He's a solid starter for between a year and two and then starts to fade.
He's solid for the whole length of his contract and a majority wants him renewed (I can't just say is renewed while it looks like we're giving Kenny a new deal).
I'd put the percentages at 2%, 48%, 48%, 2%. Relatively low risk, almost no real chance for any type of reward. For me those aren't signings we really need to be looking to make at the moment. We aren't going to go forward making those and do we really want to hold where we are?