Luck Doesn't exist, only hard (work) works
Perfect form is the most important thing to have a perfect body, it's impossible to make a painting with a big brush
Yes it is better to keep training even if your muscle is still sore.
To be a good bodybuilder you must be a good observer.
Trust me when you love something you don't need motivation.
Eat a lot and train hard, I am sure that you will succeed.