Re: Was this
In what electronic diary? Notifying whom?
Do you know how many certificates large enterprises have to manage now? It would be a full time job for someone - but if you made it that, you'd be screwed when they went on vacation or quit and the reminder from their electronic diary went to /dev/null.
The whole system around certificates is irretrievably broken if you require humans to be in the middle of it. It has to be automated - a subscription service that automatically updates. We will never see the end of such issues so long as humans have to be "reminded", because we are fallible. If the certificate for some weird page hardly anyone visits expires, it might be weeks before the company is notified. If the certificate required for mobile data to work at a large provider expires, it could do a lot of damage in the hours required for the problem to be diagnosed and corrected.