conjunction else?

[Yonsu99]

While it is acceptable to use such conjunctions to start a sentence, you should still use them carefully and efficiently, else your text might become choppy.

I think 'else' has to be replaced with 'or else' as in "Hurry up or else you'll be late." or with 'otherwise' because by definition, 'else' is not a conjunction. But is it common mistake to use 'else' as a conjunction?

 

[MikeNewYork]

I agree that "or else" is better, but you will run across the usage you have posted.