Sagot :
because daedalus was the only one that can kill the minotaur and because he was extremely mad since her daughter princess Ariadne was gone :D
The accurate answer was King minos knew that Daedalus helped Theseus escape and slay his son the Minotaur from the labyrinth and escape from the island of Crete with his dauther Ariadne,and got totaly angry at Daedalus