Loop “Forgets” to Remove Some Items [duplicate]

Answer 1

Others have already explained the issue with your code. For your task, a generator expression is easier and less error prone.

>>> text = "Hey look Words!"
>>> ''.join(c for c in text if c.lower() not in 'aeiou')
'Hy lk Wrds!'

or

>>> ''.join(c for c in text if c not in 'AaEeIiOoUu')
'Hy lk Wrds!'

however, str.translate is the best way to go.