Hi yeah so I'm engaging in my weekly hater hours. Jason at his core is a compassionate person with a strong moral compass and a need to help people. From his origin in Batman #408 all the way to his death, he was a passionate, driven, smart, and empathetic kid. After his return, yes he killed people, but he also believed in harm reduction and protecting victims. Jason was always going to be a hero, whether that was at Batman's side as Robin or through serving his community or by pursuing a career in social work, law, medicine, education, etc. Jason was to his core someone who wanted to help, and that selflessness got him killed.
From his very first appearance, Tim was selfish. He had an enthusiasm and naïvety to him, but at the core he was arrogant and self-centered. He's often quoted with "Batman needs a Robin," but his actions indicate a philosophy of "Robin needs to exist." He gets disappointed and frustrated when Dick, 21 years old by the way, refuses to leave the life he's built for himself to play into Tim's fantasy of Dick being Robin again. He is over-confident, crosses clear and obvious boundaries, and steals a dead kid's suit because he thinks his vision of reality is more important than a dead child and his grieving family. Even as he continues as Robin, he remains arrogant, he makes frequent mistakes that could have gotten him and his partner(s) killed, he is blatantly disrespectful to Stephanie both before and when they're dating, he violates people's trust, he acts in his own self-interest, and he revels in his own skill and cleverness without regard for the many, many times people have gotten hurt or nearly hurt because of it. If Jason hadn't died, Tim would have had absolutely no motive to become a hero. He had no innate desire to help, just the selfish belief that Robin needed to exist and the sheer audacity to force himself into that space (and he doesn't even do a good job of it narratively, though that's more on editorial and writers than Tim)