Five "Golden Rules" of HiFi?

1) Make sure you are listening to music, not sounds. If you don't love music, you are wasting your time and money.

2) A system is only as good as its rooom. Spend as much time as you can optimizing placement of speakers and components. Moving a speaker 3 inches can change the sound more than a new pre-amp!

3) If at all possible, buy it used. This especially applies to cables and cords. It probably does not apply to analog cartridges.

4) Understand the technology and it's strength's and limitations. If you have a tube amp, understand how to properly bias the tubes and when to replace them.

5) Trust your own tastes, realizing, in time, your system should reflect your musical values. A person who mostly listens to String Quartets will most likely end up with a different flavor than someone who is into heavy metal. This is ok., no one has a system capable of reproducing a live perfomrance perfectly, they are all colored to some degree, and that's just fine. You know, some people like chocolate, some like vanilla; neither of these is "right"

Add to the list: Enjoy live music as often as possible and support local musicians.

I like rule #1; but that's about it, from this list. Chris' "hearing as many different systems" would have to be modified to "owning,same"/for me.
Trying horns and set amps taught me a lot. While horns and set-amps have their pros and cons;they taught me a lot about what my previous system wasn't doing. BUT, I had to live with this system for a while and experience it. What I had before set me up for this experience--then what you gained from this helps you on the step after. I guess many don't have to take the baby steps I require. While I am quite happy now, I don't expect I have reached the end of my journey.

I object rule #4 and #3 as well
Instead #3 repeat #5 twice.
#4 replace "speakers" with "phono cartridge"

1. In six months of buying eggs and stapling the cartons to the wall in your listening room, plus buying a throw rug, you can do more than buying the most expensive cords.
2. The best gear is not always the most expensive, or coolest looking gear.
3. Power conditioners work. Really.
4. If you can't have a conversation about music with your hifi dealer, find another dealer.
5. Reasonable budget, over the longest term.