Ibrahim Afellay, Pedro, Christian Tello. If you're a winger at Barcelona and not a nailed on starter you will be linked to Liverpool. And then you will be linked to Liverpool again. And then when you move on somewhere not-Liverpool your replacement will be linked to Liverpool. The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun. So it goes.
You can add Alexis Sanchez to the list. He's been linked before. Now he's being linked again. And chances are he'll be linked a few more times before his time at Barcelona comes to an end and he heads off to join some other club that almost certainly won't be Liverpool. The 25-year-old Chilean international, though, at least makes for one of the more exciting Barca wingers who are repeatedly linked to Liverpool but won't be coming to Liverpool.
Along with Pedro—who hasn't yet been connected to Liverpool this year, but give it time—he's a player who would arrive ready to step into the starting eleven and has spent years playing a very similar brand of football to the one Brendan Rodgers has embraced. As such he's at least a more exciting link than the likes of Afellay in the past or Tello before him this summer. Still, it's hard to imagine these latest rumours developing into anything.
Linking Liverpool to Barcelona attackers may be a well established summer pastime, but the last time any such link has actually ended with a first team player making the switch from Catalonia was in 2004 when Luis Garcia arrived at Anfield for £6M. Love the rumoured move or hate it, when it's a Barcelona player being linked, the wisest course is generally to shrug and ignore it. When it's a specific player who's been linked repeatedly before that goes double.
So. Alexis Sanchez won't be moving to Liverpool. Given the history, though, both of Sanchez being linked and of Barcelona wingers in general, it wouldn't have been a proper transfer window if he hadn't been.