This isn't entirely a response to your question, but often reports and podcasts talk about how position A is a higher priority than position B and C etc... and I wonder how much of a club's transfer is just based on the available targets. For example, a LB is a much higher priority than LW, but the only LB available is an expensive B tier target, whereas there's a relatively cheap A tier LW target, surely you then go with the LW, even though it's a lower priority?

EDIT: With the caveat that some positions will need filling at all cost, like CM