Ignite and Shields

This is just an idea I was pondering after playing games as diana and against some champions that generally have the ability to shield themselves or others. I feel that ignite's effectiveness has decreased drastically (apart from the vision it grants) due to the shielding that people can obtain. I know I would end up dying more during games, but I personally think ignite should burn green health only. It just doesn't feel good pumping damage into a champ like sylas, igniting, and then having nothing else happen. Curious to hear thoughts and a discussion on this. If you are going to downvote, I would love to hear why you don't like this idea.

Cheers.