Everything is relative. Many years ago I started to study blackjack and set out with a very modest bankroll. $800. I am not a professional but I probably play more hours then most professionals. I take the game very serious and study/read something nearly every day. The internet has been an invaluable source of information once you weed out the garbage. I am not a theorist, I am a player. My play has steadily grown, as has my bankroll. I'm super diciplined and will not play big at any casino that has marginal rules. I will play enough to cover the comps such as flights/suites/meals but will play next door to make the money. Some management companies are more generous then others but their rules make it tough to win. I am a grinder. Just knowing I can beat a casino time and time again is really the thrill. I mix my play up. Sometimes at $10/$15 tables, spreading 1-30 or more and sometimes at high stakes spreading 1-20 or more. My game is 6 deck but I enjoy double deck with decent rules. It's not always fun when you flush 10-20k but it happens. I will quit playing the game only if I bust out and have to begin using my earned income from any other source than gambling. I am a rather frugile individual except at the tables. My adrenaline doesn't start pumping any more until my bets exceed the $1800 level...don't ask me why it's $1800 except that I have a routine that I run that bet up to $5000 if catch 2-$1800 winners and the count warrants it...anticipation. But if I run into a rough patch where my bankroll drops by50-75k...I focus on the smaller tables with bigger spreads to replenish my ammunition. I find that I can spread 1-50 at times in low stakes pits and pick up 3-5k with little chance of losing because of the low minimums. It may take several sessions but looking at my log,it's effective for me. Remember, if you bet big, you win big, but you also lose big. I rarely run long losing streaks except for the months of October and November regardless where I play. I'm always on fire Jan-May regardless where I play. The hardest thing to learn is not to change your style of play based on winning or losing. Don't turn conservative(start counting your winning) and don't plunge either (over betting). I see it happen to players time and time again. Very few players have success over the years. I see new faces every6-18 months. I don't know if they burn out or bust out. I am a loner and that has extended my shelf life. My wife is an excellent video poker player and most casinos see her as the bigger player even at my level primarily because I work very hard disguising my wins.
Also, most of the experts are not big players and the honest ones admit it. I am not an expert...I am a player.