bag holders

Don't be left holding the bag.
Price bases at resistance (in the following examples, could just as well be support)
Anxious gamblers jump all over the bid to get in at the base (b/c "it's going to break out")
Price retraces to shake out said gamblers before continuing higher.

RIG :  Yellow dot line is the day's Open coinciding with previous day's support (now turned resistance).    A good example of why not to buy the breakout itself, but to wait for a retrace.

FCX: didn't make it to vwap but instead volume showed support at a previous pivot

MON: a great example of what to look for, including the volume coming in at the retrace once the breakout occurred.