How should you treat your tubes?

Tbg, I didn't say the SS amp caught fire. It caused a woofer to start burning. I was there, we started smelling something burning. We naturally thought it was the electonics but as we investigated, it was coming from the speaker. The paper woofer had a burn hole in it. I think the explanation was that the amp was leaking DC or something like that. I can't imagine how a SS amp could catch fire. What's to burn? If the woofer had led to the grill cloth ignitig and the speaker was close to curtains, Ba-Da-Bing.

Buying used these days with people modifying, bypassing fuses etc, just be sure you know what you have plugged into your wall. If people want to play golf in a lightning storm, that's their business. I just think you should be aware of the possibilities.

Lot of good responses. Seems like it comes down to 2 things. What will make it sound the best and what will make it last the longest. For sound, leave it on 24/7 for a week or even a month, then try cycling it. Decide for yourself if it makes any difference. For longevity it's got to be leaving it on BUT what if the difference was 10 years for on/off or 20 years always on? Do you really think you're going to keep it for 10 or even 20 years? I like Nelson Pass's philosophy: One day it will break and you'll just get it fixed.

For myself, I cycle. Most of us will go thru our whole life without a problem but I do not want to be that one statistic that comes home to see Firetrucks in front of his house. For sure tubes but I've seen evidence of a speaker catching on fire with a very well known SS amp.