Jose Mourinho has been fortunate in his football career. He started his coaching career as an interpreter for the English coach Bobby Robson in Sporting CP and FC Porto. He found fame in FC Porto as a coach when he won the Primeira Liga twice, a Taca de Portugal, the UEFA Cup, and the UEFA Champions League. His experience in Chelsea was a bittersweet experience and his career took another lift when he performed another miracle after he moved to Inter Milan where he won the Serie A, the Coppa Italia, and the UEFA Champions League. His coaching career was not prosperous in Manchester City and Tottenham because he failed to replicate his performance although he won some trophies. Now in Roma and has accomplished so much. With little budget, he has won the Europa Conference League and a silverware at this year's Europa League and a ticket for next year's competition. His career is filled with ups and downs but winning a Europa or Champions League before retirement should be a good parting gift for the "Special One".
I wouldn't call him "lucky" but he is not really showing his old self neither. This was the guy who won it all and then went to Real Madrid and be amazing there as well, then whatever happened to him and his career took a dip, from united to spurs to Roma, it all went downhill. He is doing fine right now and there is nothing wrong with managing Roma, but this was the type of manager that PSG, City, Bayern, Madrid, Liverpool etc etc all the big clubs of the day always wanted, and nowadays he can't find a job at the big boys table.
The fact that he won conference league last season is both great achievement but also shows that he is at tier 3 level right now and that's not great, took them to tier 2 finals which is nice but still not managing a team at UCL level.