You see them first
There is a specific satisfaction in watching a player for a season and a half before he becomes a name that gets discussed everywhere, and Portuguese football offers it more reliably than almost any league in Europe. You notice the things that do not survive a highlight package: how he defends when the game is going badly, whether he keeps taking risks after losing the ball twice, what he does in the eightieth minute of a bad-tempered away match.
By the time the wider audience arrives, that context has usually been flattened into a market valuation and three clips. Having watched the ordinary weeks is what makes the eventual sale feel like a story rather than a transaction.
Accepting the departures
The obvious objection is that supporting a club whose best players leave every year must be exhausting, and for some it is. But the alternative on offer is not a version of these clubs that keeps everyone; it is a version that keeps nobody because it cannot fund itself. Once you accept that, the summer stops feeling like loss and starts feeling like the reset that makes next season legible.
What I would push back on is the phrase shop window, which implies the football is incidental to the trading. Watch a Lisbon or Porto derby and tell me the ninety minutes were a marketing exercise.