They really hate Happy

Happy, who was Tony Stark's security detail/chauffeur later turned head of security for Stark Industries, was in charge of asset management and oversees the transfer of Stark property from Avengers Tower to the group's new facility. The theft of the Ronin suit and him ignoring warnings about the transport being in danger in Homecoming, leaving Peter Parker to clean up his mess just makes Tony's decision to appoint him a high position look stupid. He's clearly not up for the job of looking after Avenger assets or keeping things from falling into the wrong hands.