I think that Steem Power is the best metric to measure success by on Steemit, however you define success. Is that your ability to earn money for yourself? Is that your ability to gift funds to others? Is it a hybrid of those two, to boost your earning capacity so that you can gift more? A higher Steem Power number helps you to achieve all of those goals.
I did a post a week and a half ago (I Now Have X Number of Followers!) in which I said that I'd stopped caring all that much about the number of my followers but was going to instead be a bit obsessive amount my Steem Power number. As of today, I've gone into four digits. Huzzah!
I don't have classic OCD symptoms, but I do think that if you're on Steemit for the long haul, your SP number deserves a lot of attention.
Steem Power is of course what you use to upvote or flag posts and comments; it's the "fuel" that runs the site on a day to day basis. And it also helps to increase your curation rewards. For most members, curation rewards are probably negligible compared to their earnings from posting, but whales with lots of SP can do quite well for themselves simply with curation rewards.
But having Steem Power does more than help you with voting and curation rewards. Having more Steem Power earns more Steem Power. There's a sentence in the FAQ that newbies might not have noticed, "STEEM tokens that are powered up to STEEM Power earn a small amount of interest for holding." It's not a lot, and I wasn't even aware of it until about six weeks ago when, as I was looking at my wallet page, my Steem Power increased by 0.001
I did not pop a bottle of champagne then and there and I've yet to figure out exactly what the interest rate is, but now that I'm at 1000, it looks like I'll be earning something like 0.2 or 0.3 SP per week. So the annual interest rate is maybe a bit over 1%? Granted, nothing huge, but interest rates are low pretty much everywhere right now; a bank savings account in the United States is probably earning only slightly over zero, and some European countries actually have negative interest rates, absolute economic insanity. Effectively paying banks to hold your money???
I did a little experiment. Went to steemwhales.com to find a whale with a lot of Steem Power. Go to the @freedom wallet and take a look at the Steem Power number. Over 7 million SP. Yowza! Then refresh your browser. Refresh again. And again. With each refresh, that SP number goes up a bit. Very unscientifically, I refreshed the browser about a dozen times while using my iPhone's stopwatch feature and then crunched the numbers. It looks like @freedom is accruing something like 10-12 SP per hour, or ballparkish 250-275 per day. I could retire to the South of France on that kind of money. As an aside, who is this person? No posts, no comments, no recent curation. WTF?
About half of the SP that I have is what I've earned here over the last 3+ months, about half has been purchased with Bitcoin. Going forward, I'm hoping to do more earning and less buying. A boy can dream.
BTC = 1P535cxV1SXkPWj1GAqxv6PqHuaCBnsqJ2
LTC = LSQNA1bCUDXKBfN5bewzBngTczxDBxCQkL
ETH = 0xB86A902A1bedF3b47b20edB5f35218k7d1k91aA66F