Some of the players in the team are multiple time CL winners, without losing a CL final.
So most are used to winning this competition and other big competitions (Euros, WC, Copas) and it's not so much a mental block as it is physically being able to cope with the intensity of hostile environments.
Both Roma and Pool ran us off the park by as much as 15 km at their grounds, and somehow the Camp Nou factor for some reason nullifies that in the home legs. Both Roma and Pool self destructed at Camp Nou with some Messi magic in the latter which is just individual action. Again, we didn't play them off the park or anything.
My thinking is that it's simply the end of an cycle with these seniors. They don't have the physical and mental hunger anymore. It's also why those "unknown" youngsters did so well yesterday while I'm sure our seniors would have struggled on Italian soil, again.
One thing I'm pretty amazed by with RM during your CL run is that there were hardly any ties you were complacent. I can only recall Wolfsburg, Schalke, and maybe City SF. Part of it is the special standing that the CL has for your club. Only Milan in their non mid table days prioritized it similarly.
Don't know if it matters how often these seniors won if they succumb to recency bias and end up thinking 'here we go again' i.e. Alba (although he's not the multiple time winner, only Messi, Busquets and Pique are) during away games.
It is the end of the cycle, which is why I really personally think it's silly to place as much importance on the manager as some people do. Sure, he's important, but he's not going to change the performance trend with these 30+ players if they're not able to do it on their own. Benzema is impressive primarily because he did it regardless of who was the coach, which shows he does have some actual class as a player and a leader who needs to at least try to be consistent all season. Who does that in Barcelona? Only Messi really. Pique is a fuckwit half the time. Busquets gets outpaced by every other scrub, he can't rely on his pressing avoidance mastery at this age, he's no Modrić whose style at least allows him to enter spaces and introduces unpredictability.
The complacency is something that got rooted out by Mourinho who set all of the experienced players straight after the embarrassment in 2009 having spent all the big money only to get the same result for the same reason in Round of 16 of the CL. And Raul and Guti got shipped out having pretty much been only staying in hope to bag another CL off the backs of new transfers. After that it's been 8 or 9 straight semifinals. Albeit all with a ruthless machine of a player who wouldn't be happy with any tally of trophies he won - the attitude which was important for the rest of his mates. Marcelo in the recent Players Tribune described it best - when Ronaldo would say "am I the only one to have butterflies in my stomach", it was liberating, because if he did, it meant a lot for your own confidence. When that kind of guy is absent, raising your game in the face of doubt and adversity goes away.
But I'm not quite certain if complacency is the right word to describe what happens to Barca either. Part of me thinks yes, part of me doubts it. I always think it's the easiness with which Suarez and Messi give up and fail to channel any passion they may have to their mates, this feeling that they have to rescue the team, that the main way to win is to take the ball from your teammates and show them how it's done. Suarez isn't even the right guy to try and inspire others. And it's disappointing how Leo just kind of gives up many times as if to say "come on guys, I've done all this at Camp Nou and now you can't even defend a corner"? It's impossible to absolve him and put it on the manager who's meant to come up with a scheme to prevent that. There ALWAYS needs to be a manager on the field, an extension if you will. And Messi as captain isn't cut out for it.
You can't do half measures and come up with excuses to retain finished or 80% finished mainstays like Pique, Busquets, Suarez, Rakitić.. Has to be a clean break if a sporting project is your priority (which it clearly isn't under Bartomeu). It is no coincidence Real Madrid played better football when the team comprising Llorente, Ceballos, Vinicius, Asensio, Reguilon etc was fielded ahead of the vets. Indeed as you say it's absolutely the same effect last night against Inter. But Madrid's vets are a bit more humble. Marcelo accepted he's not the same guy. Modrić is accepting of it as we speak starting 50% of his minutes. It doesn't take an entire team, but certainly the big names that the young guys look at must be moved. There is no place for Busquets, Pique and Suarez in this team despite them being adamant that they play. As long as they're here, you will make the same mistakes and succumb to the same traumas of Paris, Rome and Anfield. Because they're the main men who caused them.
[MENTION=21648]Centauri B[/MENTION]
Liverpool were almost never losers on the European stage. The only time you could argue that would be when they finished 3rd in groups and got eliminated straight after in Europa League under Rodgers. Every other time they go deep in the competition. You can't ascribe them to being losers based on just that. They're a cup team, but they're not losers.