It's been designed to be hard to track. Just because the infrastructure is a little hit and miss and the people are overall poorer doesn't mean it's impossible to reliably manage supply lines. The problem is corporations from the "West" don't want to know where the stuff is coming from because they know damn well it's sweatshop labor, minors, political prisoners, and who knows what else. That's why it's so fucking cheap.
Google knows my fucking shoe size at this point: if they, or Apple, or Samsung, or any other company wanted to know, they would know. The problem is they don't know because when people ask uncomfortable questions, they just shrug their shoulders and go "well we aren't responsible." Fuck that. They should be responsible.