What would be the most important concept I would explain to someone just starting out recording music? There're a lot of things I'd like to say, but one of the most salient is, "Learn to retain a proper perspective between individual tracks and mixes." This advice, which I must have absorbed along the way years ago, is key to the recording process. Why? Let me give you a terrifying example.
Decades ago – not long after Jackpot! first opened – I picked up a last minute, two-day job that I was able to sandwich in between some longer sessions. Ostensibly, it was for a quick demo, and the drummer was a good guy; I'd met him via another band I had recently tracked. There was to be a producer on the session – not something I had much experience with back then, but I was intrigued at the prospect of working with anyone that might have interesting ideas and studio experience. On day one, the producer was nowhere to be seen. I set up, tracked the basics, and did some of the overdubs. When we met up the following day, the band's manager was present. She'd heard that the session was going well, so she announced that these were no longer "demo" recordings, and that from now on we'd be aiming for "radio ready" productions. I thought this was odd, as I wasn't holding anything back or attempting to record the band in some fashion that wouldn't sound good on the airwaves. But I was honored that they appreciated the sound I was getting for them, so we moved on with the overdubs.