Someone is a pessimist for a reason. It could be their fear or all the misses in previous attempts or people around them. Does it mean they have no chance to progress and get over it and rewire themselves?
Our mind is our treasure. It acts as we guide it. We can reshape it with hard work and lots of self-belief. We can change our mindset. Add a positive reason to it. We start seeing the world around us as loveable.