[deskpro]

Why are ATMs not 100% flat with 3 holes - for a keypad, note delivery and a hole for the bank card to go in. A skimming device can then not be added without making it very obvious the ATM has been altered.

An ATM could also have a video camera installed that monitors the area where the card is entered - if something changes the ATM does not work and a warning message is displayed.

[Cakez0r]

That wouldn't stop somebody from adding a flat facade over the whole ATM.

[willvarfar]

I've seen ATMs in the Netherlands that have a semi-transparent backlit plastic facade so its very obvious if anything is stuck on the front.