Pain and suffering are not the same thing.Pain is the sensation from the body. Lose a leg and it arrives on its own, like electricity in the nerves, and you cannot argue it away. Suffering is the interpretation you add on top: that you will never run again, that people will see you as broken, that you should have been more careful.
An animal feels the pain. It does not carry the rest. Those extra layers need a conceptual mind, because they are not about the body surviving. They are about you surviving as an idea of yourself.
That points to a more useful question than whether suffering is necessary. Ask what a particular suffering is actually useful for. Some of it does move you to act. But some does nothing for you: neutral at best, working against you at worst.
Suffering drifts toward useless as it becomes more conceptual. Say you have an exam in a month and you are already stressed about it. The exam is not happening now. It sits in a future you are constructing, and it stands for a diploma, which stands for status, a job, and on down. Each layer is an invention, and each invention brings its own share of suffering. You can plan for the exam without paying suffering on every layer of that story. The event itself is a non-dangerous thing, a month away.
This is easiest to catch where the concepts pile up, because there you can watch yourself building it: the life-story layer, the status layer, the career layer. You keep building because some part of you assumes it helps. Test that. You can prepare for something difficult without suffering about it now.
You already dislike wasting your resources. Point that same instinct at the most conceptual, least useful suffering you are carrying, and it gets easier to set down.
During the week:
Pick one thing you are suffering about that concerns a future event, a goal, or a desire. Name the layers between you and the plain event: the imagined future, what it says about you, and what you expect to follow.For each layer, ask two questions.
Is this happening now, in my body, as pain or real effort? Does suffering about it help me prepare or act? Then find the most conceptual layer, the one furthest from anything happening now, and let that one go first. Notice how your experience shifts.