The Possible Backstory of Galra
Actually nobody knows what Galra was or if it was always evil. But I am left to speculate at the midseason revelation to the final revelation. So first we have Daibazaal (Zarkon), Sincline (Lotor) and Honerva (Hagar). For everything else, Voltron fans may have been shocked to learn the startling truth about the interconnection of these three characters.
For Emperor Daibazaal looking at the fact that Honerva is actually the emperor's mother, it is highly possible that the previous emperor of Galra took a mistress. Maybe Daibazaal like Zanbazil has a retarded half-brother. For one, I think that Honerva even without revealing that she was his mother assisted Daibazaal's ascent into the throne. So pretty much, while Honerva was always serving Daibazaal, for some reason she never revealed she was his birth mother. So pretty much, he grabbed the throne by force and turned Galra into a wicked empire which he has no mercy for anybody. Pretty much, he took the throne by illegitimate means and he was afraid of losing it. I think his cruelty to everyone is because he has probably foreseen his own son would get rid of him, maybe he did get rid of his own father after all.
For Sincline, I really didn't expect him to be half-Altean since some Galrans weren't scaly. What is known was that Daibazaal took an Altean woman by force and may have even married her at some point when was probably in his 30s. What isn't surprising is that Sincline's mother looks like Farla which causes the lust factor then again, Daibazaal is always seen having blonde slave girls and so is Sincline. Just made me think- why in the world isn't Sincline aware that Honerva is his grandmother as well? I guess royal records of the adultery of the previous emperor and Honerva were erased and maybe back then, Honerva looked much different but was still a Galran. For me, this is pretty stupid that Sincline would not believe he is half-Altean even if he saw his mother's image looking like Princess Farla. =P