"These German mercenaries had such a reputation for unprincipled, ruthless violence one chronicler remarked that the devil refused to let landsknechts into hell because he was so afraid of them. This infamy was not undeserved as it was not unknown for entire regiments of landsknechts to swap sides in the middle of a battle if they were offered more money or to desert en masse when there was no more gold to pay them." - A certain historical website
"These German mercenaries had such a reputation for unprincipled, ruthless violence one chronicler remarked that the devil refused to let landsknechts into hell because he was so afraid of them. This infamy was not undeserved as it was not unknown for entire regiments of landsknechts to swap sides in the middle of a battle if they were offered more money or to desert en masse when there was no more gold to pay them." - A certain historical website
If anything, Landsknechte were known to be brave and loyal. A few times they rebelled after they didn't get paid but never switched sides. It was italian Condotieri, who were typical italian cowards and traitors constantly changing sides and were whooped by Landsknechte. Only in later XVI century their discipline start detoriating and because of technological and tactical advancments they became obsolete.
