All teachings from a Lama are to benefit us and most of us due to our conditioned living in fear of losing, we may respond better with wrathful means.
I always recall the first thing, a parent would tell a child who has first learnt to walk, "watch out or you will fall". Out of care and kindness, the parent has indoctrinated fear into the child. We live like that, so out of the Lama's desire for us to transform, He has to use the same method we are accustomed to.
However what I have observed is that many of us do not really respond in the same manner and I have great respect for Lamas who do so much for us and still have hope for us.
In whatever method our Lama/Guru use on us, learn the deeper meaning of our own faults, delusions and our vain protection of our ego and do our best to take on the challenge and get rid of them. The result is a happy you, so why not? So beneficial.