weird ice nova build question

Hello, i've been trying to make a viable ice nova build, which was supposed to work around freezing all enemies in order to stay alive. But i've encountered something strange. I noticed other players with higher DPS, and very low freeze chance still get a higher chance of freezing monsters than I do(with 55% freeze chance). Is the threshold for an enemy to be frozen based on their HP, am I missing something? how can i make my build freeze more bosses? any item suggestions or passive allocations are welcome.

have to break their damage threshold in order to be able to freeze