Krayt is one Sith, it is quite different than other orders and he did suffer betrayal. Jacen' reign was too short to let the problem occur. The ancient Sith Empire also involves killing master especially as the Dark Lord of the Sith' apprentice, Sadow killed Simus, Nadd destroyed Sadow's spirit and Kun destroyed Nadd's. In TOR many powerful Sith kill their master because once you do it you can succeed his/her powerhouse, including the Dark Council seat if he/she is a member. Darth Thanaton also said "every sith want to kill their master". Sure it's not all of them but at least the majority in TOR's era wanted to do so.
I see it as less as a Tennant and more as a result of the psychosis that involves prolonged darksider mentality/mindset, sith usually kill their masters because they are the closet individuals to them and are convienent outlets for their rage/madness/ambition whatever. Or kill their apprentice/master in defense against their aformentioned emotional relation's psychosis. They dont kill their masters because its the sith way, they Kill them because they are unbalanced individuals, Bane cloaked thoes umbalaced tendecies in the veneeir of culture. If you Go full Darksider in Tor as a Sith Warrior your apprentice doent want to kill you, she wants to have your babies. She isn't the only sith emotionally "attached" to her master in that mannor.
Maul retrieves/saves his brother from being forever frozen in carbonite because: "he is useful"... so there's that.
They kill their master to 1. Become the true master 2. Succeed their master's position and powerhouse 3. Prove they are more powerful. Sure, Jaesa said she would not but even if she could keep it that's just 1 individual. Even Xalek said something like "One day, the apprentice will be come the master". And it's not like Malak didn't want to kill and surpass his master, he wanted and tried but failed.
But technically they didn't become more powerful than their Master. Brute force does not make up for the cunning and manipulation that Kreia/Traya exercised on everyone through out KOTOR II. Their victory was but a single moment that came back to haunt them, as Kreia trained the Exile, and the Exile defeated both of her apprentices.
