A good HF antenna is –
- one that allows the OM to log QSOs in their log.
- meets good engineering standards not a safety hazard to others or yourself not installed in a manner that might needlessly cause RFI to others.
- fits in with the OM’s budget.
- fits in the space available.
a 3 element Yagi up one wavelength on a tower never hurts a ham but in real life it isn’t something that is attainable by all for different reasons fortunately much of successful HF operating is operator skill and consistency. So put up the best antenna that you can and get on the air!