We're seeing the exact same trading setup in shares of communications infrastructure firm Motorola Solutions (MSI). Like SAPE, Motorola is forming an ascending triangle trade, in this case with resistance at $67. A breakout above that $67 price ceiling is our buy signal in MSI.
Why all the significance at $67? It all comes down to buyers and sellers. Price patterns are a good quick way to identify what's going on in the price action, but they're not the reason a stock is tradable. Instead, the "why" comes down to basic supply and demand for MSI's stock.
The $67 resistance level, for instance, is a price where there has been an excess of supply of shares; in other words, it's a place where sellers have previously been more eager to step in and take gains than buyers have been to buy. That's what makes a breakout above $67 so significant -- the move means that buyers are finally strong enough to absorb all of the excess supply above that price level.