There was also the problem of accessibility. The A380 is a HUGE airplane that demanded a lot of ground support. Airports had to modify their runways, taxiways and gates to accommodate the monster. That severely limited the number of destinations the aircraft could visit.

Then there's the problem that it's very difficult to fill up such a huge plane on lesser popular routes. It's much better to use multiple smaller medium to long haul aircraft that can land at any medium sized airport and fit perfectly at the gate, greatly increasing the number of destinations and departures available to flying passengers.

The A380 was conceived at a time when huge aircraft were still very popular, but the market and technology had both changed by the time the plane was put into service.