It all depends on what you mean by "engineering". Some people mean designed for reliability, and some mean designed for performance, for example. For example, pretty much all modern BMWs are interference engines, meaning that pistons and valves are physically capable of colliding. Packing them in like that gives a performance and efficiency boost. Not an absolutely massive one, but decent enough. It allows more power with a smaller engine, which means weight savings, etc., etc. The problem is that if anything goes wrong with the timing chain, the engine rips itself apart. It doesn't even have to break, just end up a bit too stretched or misaligned because some of the fiddly little pieces that hold it in place fail/come loose/crack/etc. Basically it means that you really have to take the maintenance schedule seriously about replacing the timing chain at the scheduled intervals. Except it also means that, when the chain is replaced, you (or the mechanic) absolutely can not mess up because you don't get a second chance.
So, basically, for BMW, for the interference engine situation, and many other things in the car, they have chosen the definition of engineering where everything is sacrificed for that little bit of extra performance/efficiency that mostly only applies if you're racing the thing. So, like you say overly complicated and fussy, and also strict maintenance requirements and strict requirements for expertise for the maintainer otherwise things go badly wrong.