This is certainly a personal feeling, and in my case, I can list these:
Essence mk1: too expensive for what it was, few features, B&O helping it die faster
Beosound 3: expensive, heavy for a portable radio, fragile top panel
Beolab 5: far too expensive, fragile, mediocre dealer to say the least, anxiety-provoking. Here it’s the global experience, not the product alone, that has worst value for money.