In the beginning Dukat was just your standard Cardassian heavy portrayed by an extremely charismatic actor. He had great chemistry with Sisko and Kira. Then the Cardassians were portrayed as evil because they brutalized the Bajorans in the labor camps and they had to defeated through terrorism before they abandoned the planet. Dukat was the face of that kind of villain, but he could very charming.
As the show evolved and the Dominion and other new elements shifted within the show, the producers gave Dukat different things to do, which softened his character. By season 4 the Cardassians were allies with the Bajorans and the Federation, Dukat was fighting the Klingons, and he had a half Bajoran daughter.
Then in season 5 when the Dominion War heated up, the producers decided that Dukat had to end up as the evil Nazi that they always thought he was. He became the biggest deluded egotist of the entire galaxy. He betrayed the Alpha Quadrant to obtain power through an ill-founded alliance with the Dominion. Then he lost a crucial battle, saw his daughter murdered, lost his mind, and became the leader of a Bajoran religious cult.
I don't think the producers really did the character justice. His evolution didn't feel natural or organic to me. But Marc Alaimo was always fun to watch.
Oh they, Ira Behr and the bunch, didn't and I never thought they knew what they had in the character of Gul Dukat. I thought the Cardassians were more like the British during times of the British Empire and their tyranny over the Irish and the Scottish and their brutality and level of ruthlessness during their reign. What Cardassians had which was during the 1st through the 3rd seasons of DS9 was the ability to implant subtext to everything they said. To our heroes they are flat out "lies" but in accordance to the nature of the series at the time--when it was good-- the Cardassians reveled on mind games. The truth is in plain sight if our heroes look a little deeper; the display of visual storytelling during those seasons were outstanding, and expressed how dangerous the Cardassians were. Gul Dukat, and Garak were the pure manifestations of what Cardassia represented, and it's not pretty because the ultimate weapon of a Cardassian is their charm. You can have a conversation with these people and forget they are bastards, and for a moment, convince you on their twisted point of view. Nazi's were NOT like this, sorry Ira read a fucking history book!
I have to give a lot of credit to the actors of DS9 who seemed to understand the premise better than the writers
at the time, and when a Cardassian appeared on the show in the beginning, all of the attention came to them.
I sensed the castration of the Cardassians started with the idiot named Korinas ("The Defiant") who was the observer of that goofy Obsidian Order which apparently Garak was in. Well, obviously "the Order" had better days and smarter people during Garak's term. And the layers of the characterizations of Cardassians continued to spiral down the Ira Behr toilet bowl when Garak's daddy does the most un-Cardassian thing and stupidly made a ridiculous attempt of attacking an alleged Dominion Homeworld ("The Die is Cast"). By that point it was quite clear the Cardassians were becoming second banana to the liquid terminator aliens, who are Odo's people, and
the wannabe Klingons who had Predator-style camouflage powers.
When Bajor made the agreement to mend their differences with the Cardassians in a Treaty ("Life Support") I had the feeling there was more to this which was going on, and there was a master plan lingering with the Cardassians. How will they play this out??? And was it possible, the Cardassians were going to make the Bajorans become more like them? I saw some hints of this with Vedek Wynn, and the very Cardassian-like Bajorans "The Circle"; I felt there had to be more radical Bajorans out there, within the mists working with our heroes. "Who is the enemy when you're staring in the mirror?" I felt the Cardassians cast a shadow the Bajorans would have to deal with for the duration of the series, but by season 4 the Cardassians were a joke. And for me, the series became that as well with more 1 dimensional Cardassian characters like Dumar, the worst Cardassian character ever written. Gosh, how the great ones had fallen? The writers & producers just didn't know what they had with the Cardassians.