Trolley on Platform at Cranmore

There is more on the left but I cropped it because of over-exposure. What remains was under-exposed; I lightened it. The colour and tone were askew too. I fiddled with them in post-production. I should have taken a reading to get accurate white balance. I should also have used a strong neutral density graduated filter over the bright area to the left. It's all elementary, so why do I keep failing?