To terminate.. or not

Solid wire unterminated. No stray strands to worry about. Just as bad as the stray strands are the loose banana plugs... killed a channel that way. Spades over bananas if you can, but bananas for simplicity. Bare wire is first choice though.

It depends on your requirements. The best connection is to solder because it eliminates the #1 problem of contact reliability, which is tension force. Obvisouly soldering is not always an option and you must connect meachanically. In which case, bare wire offers the best reliability. If it is a semi-permanent connection, like at the speaker, then there is no reason not to use bare wire. The problem with bare wire is that strain releif is next to impossible. If you are going to plug/unplug often, like at the amp, then bare wire can stress, fray, break. In which case, you probably need a connector for strain releif as well as convenience. Going back to rule #1, select a connetor that offers tension force. That would be a locking banana.

I hear so many people say that spades offer the best quality. But I never hear a reason why. My experience has been poor. Can someone please tell me one good reason why to use spades?

Now that we are on the topic, why don't they put lock washers on bidning posts? That would apply tension force to hold both bare wire and spades in place.

"Can someone please tell me one good reason why to use spades?"

Many amps don't allow bananas. I used to have Cambridge A3i amp that allows only spades (no hole in the post). Now I have Rowland model 102 that has Cardas clamp style (with one big knob) terminal for spades only. Whole new lineup of Rowland amps might have it.

Makes no audible difference make selection based on convience

Kijanki,
I had those Cardas on my amp. They drove me crazy. I had them removed.