Been thinking about this lately - most traders either don't fully understand GTC orders or they sleep on them completely. Let me break down why this order type actually matters for your trading strategy.

So here's the thing: a GTC order (good 'til cancelled) is basically your way to set it and forget it. You tell your broker "buy me this stock at $50" or "sell at $90", and it just sits there waiting. Unlike day orders that die at market close, a GTC order can stay active across multiple trading sessions - days, weeks, even months if needed. Your broker will typically auto-cancel it after 30-90 days to keep things clean, but the point is you're not constantly re-entering the same order every single day.

I see a lot of traders get caught up in watching charts all day. With GTC orders, you don't have to. Say you think a stock at $55 is overpriced but would jump on it at $50. Place your GTC buy order and move on with your life. When it hits that level, boom - order fills automatically. Same logic works for taking profits. Hold a position at $80, set your GTC sell order at $90, and you're locked in once it reaches that target.

But here's where people mess up - they forget about the risks. Market gaps are real. A stock closes at $60, overnight news drops, and it opens at $50 the next morning. Your GTC order that was supposed to trigger at $58 just executed way lower than you wanted. Volatile markets love punishing traders who set GTC orders and then ignore them. You might catch a temporary dip that fills your buy order right before the stock tanks further.

The other thing that gets people is just plain forgetting. You set a GTC order three months ago when your strategy was completely different, and suddenly it executes under totally new market conditions. That's why some traders use stop-loss limits alongside their GTC orders, or just review their open orders every couple weeks to make sure they still make sense.

Compare this to day orders - those expire at close, so you get one shot per session. Day orders are for traders hunting short-term moves. But if you're thinking in terms of weeks or months and you've got a specific price target in mind, a GTC order is your friend. You get the automation without the daily monitoring headache.

The real edge here is discipline. Set your GTC order at a price that actually makes sense for your thesis, then check in periodically to make sure nothing's changed fundamentally. Done right, GTC orders take the emotion out of execution and let you stick to your plan.