why chgrp or chown command causes file loss xattr

[root@localhost ~]# getfattr -m - -d /bin/tcpm getfattr: Removing leading '/' from absolute path names # file: bin/tcpm security.capability=0sAQAAAgAUAAAAAAAAAAAAAAAAAAA= security.selinux="system_u:object_r:bin_t:s0" [root@localhost ~]# chgrp 951 /bin/tcpm [root@localhost ~]# getfattr -m - -d /bin/tcpm getfattr: Removing leading '/' from absolute path names # file: bin/tcpm security.selinux="system_u:object_r:bin_t:s0" after chown uid /bin/tcpm or chgrp gid /bin/tcpm，/bin/tcpm loss xattr(security.capability) #/bin/tcpm provides by tcpm-kmod