don't forget a large part of learning is from mistakes

Funny things i've done and learned from mistakes:

my first engine swap i poked a hole in the radiator! - moral was to remove the radiator unless you had somone holding the engine while you were removing/installing the engine

my first track days i would constantly cooked my brakes no matter what changes i made (add 100whp via turbo and 16 x 7 falcon azenis to a car completely unsettles the stock balance of power, brakes, suspension and steering)...it took me several events to realize the stock brake system could not handle the extra speed and the extra grip (even with race pads and cd rotors with dot 4 brake fluid)...i finally had to upgrade to a big brake kit - moral here is any major change you make to your car upsets the balance and you need to factor in improvements in the other areas (i still need an lsd as once spooled inside wheels spins a nice cloud of smoke)