When Hortonworks CEO Rob Bearden took questions from analysts during the company’s earnings call on Feb. 10, Barclays managing director Raimo Lenschow put him on the spot. Lenschow wanted to know what Hortonworks — the provider of big data crunching Apache Open Source Hadoop — was going to do to stop employee attrition, given how far the value of their stock options had fallen. “Have you …