For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
Like boards I fucked up beyond repair with BGA? I'd say less than 20 in the early years, but that was 10 years ago when things were much easier, no lead free crap. 0.6mm balls were the smallest you'd find back then.
Starting off right now I'd imagine much more failure because of lead free and 0.25mm balls on the MUX and such shit.
This is the reason why you don't learn on $1500 retina MacBooks. You learn on a shitty $25 HP and move up.