Why does luther crumble and discard the indulgence he received in rome

Martin Luther was a monk who saw the Catholic Church's view on the indulgences and the wrong doings of the church as horrid. the indulgences took money away from the already poor and making them believe that paying your way for your family members to get out of purgatory would help their already dead family members. as a result he makes the 75 thesis in Latin , critising the church but soon it is translated and the reformation's actions start to speed up