Why is my Kraken fee so high?

I've noticed that the fees charged by Kraken seem unusually high when compared to other cryptocurrency exchanges. Could you possibly explain what factors contribute to these high fees? I've reviewed the transaction details carefully but still find it puzzling. Is there a specific fee structure or are there hidden costs that I'm unaware of? I'm also curious if the fees are variable and, if so, what determines their fluctuation. Understanding these details would help me make more informed decisions about using Kraken in the future.