Smart contract testing currently faces a problem:

๐Ÿ‘จโ€๐Ÿ’ป developers are in short supply, so

๐Ÿงช smart contract testers get asked to write code, and

๐Ÿ”Ž code writers are too close to the code to spot the wider problems, and

๐Ÿ“„ smart contract quality suffers, thus

๐Ÿ’ต funds are lost

I use a chess analogy to explain why developers usually only test one aspect of code.