Shares of Microsoft Corp slid on Tuesday after the surprise departure of a key executive, who analysts said marks the loss of the driving force behind the company’s biggest product.The shares were down 2.8 percent in afternoon at $27.21.

Wall Street took Apple’s executive changes in stride when they learned that Jony Ive and Eddy Cue would assume some of Forstall’s duties. It had a calming effect on everyone. Microsoft, indeed most companies, don’t have that.