Curious where the "Find People on LI" data is coming from -- is it a l...

Curious where the "Find People on LI" data is coming from -- is it a live cloud scrape of LI? Been testing the url crosscheck against Apollo and always see discrepancies...is Apollo data more stale than the Clay search / are the numbers artificially inflated? Is Clay's totally comprehensive and should we abandon using Apollo when we have lists of domains and need contacts? Any insights here appreciated, thanks!