Can you please copy paste a related build’s bitrise.io URL? Without logs / context it’s incredibly hard to say anything more helpful 
Not weird at all, as our VMs are clean MacOS installs, pretty much the same state you get when you install MacOS on a brand new Mac / when you do a clean MacOS install, while your own MacOS is most likely heavily modified with additional tools / configs. Again, without logs I can’t really tell anything more helpful so please copy paste a build’s URL and we’ll check it ASAP!