Everyone in the Resistance *knows* that Kylo Ren is an unruly hulk of a man-child who throws epic temper-tantrums. Powerful, but unruly, chaotic, impulsive, and childish - he does as much damage to his allies as his enemies.
...then they manage to steal some footage of the day-to-day running of the Finalizer.
Kylo Ren is prone to fits of temper, yes - but all it takes is one sharp word from General Hux to calm and discipline him - something that Luke, Leia, Han, and literally everyone in the New Republic and New Jedi Order failed to accomplish.
+ If Leia's heart breaks at how *happy* her son looks - happier then she can ever remember him being before.
Kylo/Hux: Managing the Unmanageable
...then they manage to steal some footage of the day-to-day running of the Finalizer.
Kylo Ren is prone to fits of temper, yes - but all it takes is one sharp word from General Hux to calm and discipline him - something that Luke, Leia, Han, and literally everyone in the New Republic and New Jedi Order failed to accomplish.
+ If Leia's heart breaks at how *happy* her son looks - happier then she can ever remember him being before.