Berkshire had a pivot where, decades back, Munger convinced Buffett to switch from investing in bad companies at a great price to good companies at a good price. Their new strategy is still active.
That said, the turnaround 'mission' you mention about still happens, but is more associated with private equity than Berkshire.
They also have a history of buying good private companies at a good price and then let the management keep cooking. This is especially relevant to family businesses that want liquidity for the heirs and good long-term (indefinite) stewardship rather than selling to some PE vulture that will destroy their legacy.
Not quite right. The pivot was from good companies at a great price to great companies at a good price (unless you can get a great price, but that’s unlikely).
Over the long run the latter is a better and more scalable strategy.