Seems that roling builds are enabled on appveyor, which is beneficial except in the case of master, where it could be helpful to have test information for each merge/commit. e.g. see: https://ci.appveyor.com/project/DrahtBot/bitcoin/builds/21360201
(Note that “Rolling builds” can only be enabled in the settings UI of a project and not via appveyor.yml and that the presence of appveyor.yml does not disable this UI setting.) https://www.appveyor.com/docs/build-configuration/#rolling-builds
