Bureau of Labor Statistics

Just trying to wrap my head around how the jobs report works and curious how this works mechanically. June's initial estimate was 147,000 new jobs but the following month that was revised down to only 14,000 so the initial estimate was off by an order of magnitude. My understanding is that this report is based on a couple of surveys of employers and households but it takes a while for all the survy responses to be collected so there's an initial report based on the first few surveys (I saw an article citing a figure that typically around 70% of surveys are returned in time to be included in the initial report) with subsequent revisions over the next two months as more responses are received.

So my questions are: Why were the initial responses in May and June so grossly misrepresentative of the whole? Why couldn't BLS detect that the initial data was suspect?

For instance if it was an unusually small sample size or if later responses were disproportionally giant employers with an outsized impact it seems those are things BLS could see from their initial data and account for in some way if only to put an asterisk next to the number saying "Our initial sample data was weirder than usual... expect larger than usual revisions in the coming months"