Showing Respect
This theory seems to be popular, at least with regard to the British population. People tend to believe this hypothesis. And William, the results of a poll commissioned by StatistaCharts revealed that almost half of the British population wants to see him take the throne, not drop it.
The Proceedings
On the internet, it is said that Diana had mixed emotions regarding Charles being the king. As little as this may be a surprise, the marriage did not really end on a positive note. When making an appearance on Panorama in 1995, she mentioned this as she spoke about it.