You'd have to define "good" and "bad" in regards to human behavior.
I've learned that most people are selfish in their core, they may do good things, or be a good person, but many times this stems from a desire to please or bring recognition to themselves. In which case I ask, are they really good?
The question is so much more than just good vs bad, and there are a lot of judgements and assumptions made when deeming someone "good" or "bad".
I'll judge myself for an example. I know that I am naturally lazy and self-centered, i can be mean to people, I lie sometimes, I genuinely hate some people. Hearing this you might consider me a bad person (of course, I only told you the bad about myself). I could make equally long lists of the "bad" and "good" I've done, but like I said, considering I'm self-centered brings into question the motives for anything "good" I do. Some would argue that the motive doesn't matter because you're still doing something "good", but that is focused on the effect, not the cause. The cause will reflect a person's nature, and the cause oftentimes, is selfishness.
I believe this is where love comes into play, when it's too difficult to judge someone's character on how "good" or "bad" they are, judge them by how they love their fellow humans. Love must be selfless to be true, I wouldn't give my best friend a hug and tell them everything will be okay in private for my own gain, that is an act of love. I wouldn't anonymously pay for someone's food because it looked like they had a bad day out of pride, it would be an act of love.
Are people good or bad? They're undoubtedly both, but they also have an incredible capacity to love, and not utilizing that love (often called compassion) is where we fail as people.
Anyway, I hope this makes sense.