My Costco Self Checkout Observations

I see that our local Costco has recently removed their self checkout systems.    That they were doing this has been reported for some time.   We experimented with these systems for some years, looking for possible marketing angles.  Many retailers continue to add the systems.  I asked a Costco checkout person why?  They said the primary reasons were to decrease checkout losses, and maintenance costs. The regular checkouts were notably crowded as we approached,  a number were unstaffed. We waited about ten minutes.