The moment your success makes you differentiate yourself from others and makes you believe that you are so much more better than the others, the seed of arrogance gets planted in your mind.  Sychofancy waters that seed to grow into a huge plant within you and you slowly but firmly (most certainly, wrongly) start behaving arrogantly. Sense of grandoise, irreplaceability and systemic over-dependency on you, makes you a legendary super-hero in your mind. People around you first start avoiding you and then they start rejecting you. Slowly but surely they pull energies around and conspire your fall, actively or tacitly. Insecurity, Super Achievements & Need for Approval contribute greatly as causes for Arrogance. Your overwhelming success could be the cause of your failure ... be thus mindful dear leader. However great a leader's achievements maybe, if he is arrogant, his downfall is guaranteed. The arrogant Manager never believes he is arrogant..he believes his team adores his performance, understands the preassure on him and actually worships him. Ever put face-to-face with truth of the venom the team members hold against such an arrogant leader, disbelief would kill him.