Worst executioner in history.

In 17th century England, an executioner by the name Jack Ketch had created panic in the people sentenced to the gallows. Here is his story. In 1683 at Tower hill, Ketch carried out the public execution of Lord William Russel, who had been condemned as a Catholic (Yes, it was enough to warrant a death sentence those days) Russel paid Ketch to make a clean job of it, and when the first blow was rendered, it merely glanced his neck, he looked up and complained, "You dog! Did I give you ten guineas to use me so inhumanly" in the end it took Ketch 4 to 5 attempts to sever Russel's head. The botched execution created an outcry, but his executions now drew larger crowds than anyone else's as the public clamoured for drama of Jack Ketch's performance ( clearly people did not have any other entertainment those days) in which victims would tremble with fear.
Two years later, Ketch was called again for beheading James Scott, the duke of Monmouth (beheading was the punishment of nobles, the common man was hanged).
Scott was aware about Ketch's reputation, and urged Ketch not to repeat it, paying him six guineas upfront and six more for a clean kill. He even inspected Ketch's axe to see if it was sharp enough. All this made Ketch so nervous that even after six blows, Scott was not dead, but writhing and screaming in agony. As the crowd roared with horror, Ketch threw his axe and challenged anyone in the crowd to take over if they could do better. The sheriff ordered Ketch to pick up the axe and finish the job, which he did after two more attempts. But even then he had failed to sever the head, and had to complete the task with a butcher's knife soaking the scaffold and nearby spectators with blood. The crowd were so enraged, that Ketch had to be escorted away for his own safety. After the disaster of the Duke of Monmouth's execution, Jack was sacked and imprisoned. His replacement was a butcher named Paskah Rose, but Rose was caught stealing a coat and hanged at Tyburn. Amazingly, despite everything that had passed, Ketch was now rehired in his place. Call it job security!