I don't find it necessary, but I haven't met everyone and maybe some people have it coming.

I think hate is unnecessary and counterproductive.

Energy spent on hate could be better used as something positive that makes you feel better. That said, like all emotions, hate is valid, but it is what you do with the emotion that makes the person.

No. I think some people actively inspire hate, and it's only fair to give them what they inspire.

It depends on the hate. Many tell me that I now have to "hate" my ex-wife. People change and directions change. The truth here is that these people are simply racist. Lets take that on into someone saying they "forgive" the killer of their spouse or their children. This is insanity and something they thing a religion taught them. I could never forgive a killer of my family. Not now or ever. I don't really think those that claim they do are honest with you. I think they say it coz "they want to go to heaven." Hate is a strong word and a prime mover for many of us to get things done. It may be unnecessary to hate in dire circumstance but it is a valid emotion.

Depends on how you define hate.
To stew with hatred or "be filled" with hatred is unhealthy
[huffingtonpost.com]

However, to analyse the event and establish a set of conditions to employ following an unpleasent experience may be necessary: for a theoretical example. Ted and his associates, the people who sold me a perfectly running car with no mechanical problems actually sold me a car that is not roadworthy. They are never again to be trusted and should be avoided - - May (if possible) have a less detrimental effect on your health.

Hate is an emotion as strong as love. You have to care very deeply to love, and you have to care just as deeply to hate. When I find myself beginning to hate, I take the time to discover why I care so much for the person I'm beginning to hate. If I didn't care for them, they would not matter to me so it would not be possible to hate them.

So, yes, I think it is unnecessary.

It's wasted energy on negative emotions. It helps nothing and hurts you not them.

It can be injurious to your health. Perhaps it can be worked out, internally, through your higher self. That takes time. It might be good to melt away hate because it would make you feel better. There are a lot of things and some people who challenge us this way...encroaching on our Joie de Vivre.

Yes, Unnecessary.

Absolutely. Hating another person is probably the quintessential example of wasted energy. It's like drinking poison and waiting for the other person to die. All that negative energy is unhealthy, literally. If I find myself feeling that strongly towards someone, I make it a point to try to wish good things for them. It's not for their benefit, it's for mine.