It surprises me that Berkshire took so long to dump GE.
Buffett usually holds for long (if not forever) periods. Given the long-term financial performance (10 years), it is clear that GE has suffered since overextending themselves in the financial space. Yes, GE has gotten out of much of the finance field, but the residual effects have taken their toll.
This is a lesson for all investors out there. Even the best investors have bad investment selections. It is just the nature of the beast.
Don't fear making a mistake in your investment selections. The key is to mitigate as much performance risk as possible by gathering and analyzing a great deal of information (Read, read, read)
Even the best have their challenges and I have all the respect for Warren Buffett
As Wayne Gretzky said, "You miss 100% of the shots you don't take."