Sultan Muhammad-bin Tughluq has been described by some as a ‘mad king’. For, all his projects like the transfer of capital from Delhi to Daulatabad, introduction of token currency, experiment in Doab and expedition to Kangra were all unsuccessful.
Not only that, his experiments set those forces into play which eventually led to the disruption of the Delhi Sultanate. Also the Delhi Sultanate was financially ruined. Despite all this modern historians point out the intrinsic merits of some of his projects. It has been pointed out by Satish Chandra that Muhammad-bin Tughluq actually wanted to establish a second capital, not transfer of capital from Delhi to Daulatabad.
Again, the introduction of the token currency was a modern concept. Where he failed was not being able to take proper measure to prevent imitation of the currency.