#1 Their players know how to get the job done

While their continental woes in recent years might be well documented, it has been an entirely different story for Barcelona domestically and the Catalans have been near-invincible in the Spanish league.
In the last 11 seasons, Barcelona have won eight league titles, with Real Madrid and Atletico completing the roll call of champions in that time with two and one titles respectively.
The Champions League is a 13-game competition that rewards teams and players who can step up to the plate once every fortnight and their performance in those 90 minutes determine their fate regardless of what they do elsewhere.
By contrast, a league campaign is a nine-month-long, 38-game, gruelling ordeal that requires optimum concentration to get result week-in, week-out and Barcelona players seem to have mastered the art of getting the job done domestically and this experience in going over the line would come in handy during the home-run stage of the season.