Armed robber defeated by his own stupidity

Stuff reports:

A man's attempt to rob a Christchurch was foiled when he was unable to open the unlocked sliding door.

Police said the man, armed with a gun, tried to rob the Division Street Dairy in Riccarton on Monday night.

He unsuccessfully tried to get into the dairy by “pushing and pulling the unlocked sliding door”, before leaving down Division St towards Blenheim Rd, police said. 

Not a candidate for Mensa then.