Why PESSRAL is not PESS

The lift industry is quite old-fashioned in electric / electronic / programmable electronic (E/E/PE) safety: they used the electric safety chain for more than 30 years. However, since the EN 81-1/2 A1: 2005 amendment, the standard allows to use programmable electronics for safety systems (PESS). Also, the code committee decided to implement a subset of the leading norm (IEC 61508) into EN 81 in order to decrease the difficulty and increase the implementation speed: PESSRAL (Programmable Electronic System in Safety Related Applications for Lifts) was born. However, due to cherry picking and skipping the basics the old and even the newest code (EN-81-20/50) makes it possible to create unsafe systems. Where are the potential risks?