No, I will often carry positions for several days, weeks even.
I attribute my high win rate to a couple of factors:
1 I trade a very small list of shares (about 6 regular tickers actually). Most of these I have traded hundreds of times. So I sort of get to know them, how they move.
2 I use very wide stops, but I will close a trade if the picture changes, rather than wait until I get stopped out. I can always have another go later in the move. I have in the past tried trading index futures with tight stops, but IMO that is a mug's game, just get chopped to bits over the long run.
3 I have a rule - no trade entries for the first 30 min after the market opens. I think this saves me from poor/hasty entries. Instead I watch and plan my entries based on what I am seeing.
On the last one, I really think every trader can benefit from analysing what works and what does not. It will be different for every trader, but for me, those early entries led to some terrible days. So I binned 'em. Sometimes I see a really nice trade before the 30 mins, and I'm really tempted, but for well over a year now, I have resisted the urge. Which I think is the right thing to do.