Always Produces Same Thing — Python 3 [duplicate]

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• How to test multiple variables against a value? 13 answers

This program, even when '2' is typed in on line 10, produces a success message. Why?

a=1
while a==1:
  b=input('Are you ready?')
  if b=='yes':
    print('LOADING')
    a=2
  else:
    print('You aren\'t ready.')
print('Go.')
c=input('Mode 1 or Mode 2?')
if c=='1'or'Mode 1':
  print('Success!')
else:
  print('BEEP BEEP BEEP ERROR')