Most of the castles in Europe were built for defensive purposes and the towers were used to spot intruders or attackers on the owners property. King Ludwig on the other hand built his castles for more romantic reasons.
While building different castles all over the region, the King started falling deeper and deeper in debt. He became more interested in his castles than matters of the state. For these reasons, the ministers of state sought to have him replaced by calling him mentally ill and unfit to rule. Having never been physically examined, he was taken into custody, and one day later died under mysterious circumstances.
Ironically, the very castles which caused his demise have today become extremely profitable tourist attractions. They have paid for themselves many times over and attract millions of tourists.