An unspecified technical problem forced the Rio-bound Boeing aircraft to turn back shortly after takeoff from Amsterdam. A spokesperson for Dutch air traffic control said the plane requested to land as a precaution and turned around over Belgium some 40 minutes after takeoff.
I follow a couple of channels on youtube that post replays of interesting radio communications between pilots and air traffic control. There are technical issues that cause departing flights to return to the airport virtually every single day. Electronics, landing gear stuck down or stuck up, engine stall, engine fire, flaps jam, a sensor says something unexpected. Every brand of airplane imaginable. Pilots are trained to navigate every possible failure mode a plane can encounter. Getting permission to carry commercial passengers requires an incredible level of training and testing. Commercial planes are rigorously engineered.
I’m not trying to carry water for Boeing, but this article describes a relatively common operation (as far as I can tell).