it is a good advice. I tried that several months ago, I fellt it is a great way toward wealth building, when i look at my equity curve, I found my equity curve is steady up trend (almost 45degree degree up). I even extended this concept to 1hr/$500, 0.5hr/$500, I started to do trading around 7:00Am, I trade crude future contract, I divided one day into 8 or 16 trading session. in every trading session, my task is to try to hit goal. most time, I can do that, occassionally I lost control of some my little trading session. the problem with this extension is we are human beings, after several micro-trading sessions, we will be tired, we will lose our focus because of mental/phsycal fatigue. so the best strategy is hit the goal, then rest a while, for example, in one minute you may alreday get your half hour goal, take teh profit, sip a cup of coffe or do somethingelse, let mental ready to do next session. I am gready guy, this drives me crazy. later i found the best strategy is maybe divide the day into the morning session and the afternoon session, if i hit the morning session goal (even 10 minutes hit my goal), I leave to take a rest, do somethingelse, be prepared to take the afternoon session.
the only thing in this strategy need be improved is: also need set a maxmum loss goal, otherwise it will lead to revenge trading or very emotional trading (try to hit goal).
most traders here object at daily goal setting or even minute/hourly, I do not agree with them. if you do not have a clear goal before you start, you already fail before you start.
of course goals should be reachable normally. not those 'one night double/triple/ten fold" goal, that is rare, in realty, they does eisxt. lots of little bio-tech stocks can produce this results, but the winning probaility is very little. $500 just correspond to 0.5 point move for individual stocks if you trade 1000shares, in half hour or one hour, for 10bucks + stocks with some volume, it is pretty normal. people often neglect those little opportunity, and they aim for those rare things, that is why they struggle all day, when they win, they lose back or more because they think their winnings are the rare ones!