A man who produced his own bike by stealing parts for 5 years from a working bike factory

There seemed to be a man who had been stealing motorcycle parts for 5 years from a working factory and assembling a motorcycle by himself. I understand that small parts will not be noticed even if they are stolen, but did the factory not notice even if the large parts were stolen?

Details are from the following.
Ananova - Man stole motorbike - part by part

Mr. Zhang who worked at a motorcycle factory in Chongqing, China thought that he wanted his own bike, but he did not have the money, so he took the parts a little from the working bike factory and thought about assembling the bike by myself . This plan started from 2003, and after five years the motorcycle of the desire is completed. Mr. Zhang became happy and immediately took this bike and went out.

Mr. Zhang assembled the motorcycle seems to be like a photo.


However, as soon as he started driving, he was called by the police and underwent interrogation, where he not only found out that he was a motorcycle without notification, he also discovered that it was an unlicensed driving. In the subsequent investigation, he acknowledged that he was a motorcycle made by stealing parts from the factory where he was working, he said he was to return the motorcycle to the factory.