Why are we told not to smile for passport photos?

It is easier to recreate a straight faced look than a smiley face. If you are returning to your own country and going through the special channel with facial recognition, the machine measures the distance between eyes and nose etc to check the person stood there is the one on the passport. Your eyes screw up during a real smile and the measurements would be different.

It is easier to recognise a straight face look

Rules...

Because the photo is used to take biometric information from. So the requirements are very strict - no smiling, no hat, it's got to be done exactly the right way to take measurements from and put them in the biometric chip in the passport.

because they want everyone to be depressed you retard

They are extremely emo and do not want any sort of fun near them

They want your natural look for facial recognition. I went through this too.

They take many pictures so they see what suits you.