The issue is when you're short the timing needs to be right (which you have no control over). You can lose money even when you're right, due to margin calls, fees, or general market irrationality in the short to medium term. When you're long (and not using margins) all you need is a cool head, and look at the price paid relative to what you're getting.
CBA Price at posting:
$119.40 Sentiment: Hold Disclosure: Held
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