Depends on the seed, a lot use some pretty harsh washing and clarifying agents like hexane that are of concern. Olive, avacado, even sunflower oil are all generally pretty good. Animal fats seen to be better overall, and that's mainly down to it being a more natural, less refined food source.
As a complete novice, why are seed oils bad for you?
Keep this as simple and concise as possible π
Discussion
Additionally, the plants only want you to eat the seed if you will pass it to a place where it can grow. If our digestion, or processing, makes that impossible, that plant makes a seed that inflamed our body and eventually enjoying a level of suffering.
I think this is probably the case with many, but probably not all, seeds. Nut oils, and seeds where the oil comes mostly from the flesh VS the pit are usually safer.
I still prefer animal fats when possible.