To maintain your portfolio at peak performance.

To pick the right stock for the long term, you should keep to:

1.  Buying quality companies
2.  Buying at the right price - potential return > 15% at acceptable risk (where the potential return to potential loss of >3x.)

Your ability to do the above is all you need to build a great portfolio that will meet your expectations.

To maintain your portfolio at peak performance, you will need to manage it well, optimizing its performance and preventing the companies that occasionally go south from damaging it.

Portfolio management chores take a minimal amount of time.

Related:

My strategies for buying and selling (KISS version)