The note from analyst Youssef Squali and his team says: "It's hard to know for certain, but some of these changes seem to be involuntary as management tries to flatten the reporting functions and streamline the organization by having engineering, product and design management functions report directly into CEO Dorsey."
Both departures come shortly after longtime COO Adam Bain abruptly stepped down in early November. Twitter also lost its vice president of ad sales, Richard Alfonsi, to Stripe in early December.
The senior-level "revolving door" at Twitter (as Cantor put it) has long been a concern for investors. McFarland and Messinger's recent departures bring the total number of top-level exits to 12 over the past year, according to a list put together by Recode. And, of course, Twitter has gone through four CEO's in nine years.
But this note puts the most recent departures in a new light, suggesting that, rather than "bailing out of Twitter," Dorsey is now proactively letting executives go as part of a restructuring.
Business Insider contacted Twitter for comment but we did not immediately hear back.
After the most recent departures came to light earlier this week a spokesperson for Twitter told Business Insider: "We believe these updates to our organizational structure will enable increased discipline in our product strategy and faster execution."