Why aren't more ua locks running deathbolt?

i got hit for a 25k .9 sec cast deathbolt today

wondering why i dont see it more often

I feel I have to go with Demon Armor and Rampant Afflictions sorta required. That leaves one, and I look at Deathbolt vs Rapid Contagion. I feel like for team fights Rapid Contagion is going to be providing a lot more pressure where Deathbolt gives a higher single target burst. I typically go with Rapid.