Say there are five sites that would normally be returned for a query and they have scores A:20 B:18 C:10 D:8 E:4. The results will look like "A, B, C, D, E". Say none of them support https, and then the search engine adds https as a positive ranking factor worth +3. Site C turns on https, the order still is "A, B, C, D, E". Now site B turns on https, the order is now "B, A, C, D, E".

Imagine instead they had added "lack of https" as a ranking factor worth -3. The rankings on the page would have changed exactly the same way.

"not having an inbound link" can be thought of as a negative without changing rankings. In the example above, if getting an inbound link from apple.com would move you up 4 points, then if B got a link from apple that would put them at 22 to A's 20. If instead "not having a link from apple" was worth -4 points, then A would be at 16 and B at 18.