The Taylor First Single Phenomenon - 20 years running

So I know this probably a commonly discussed thing but why is it, since seemingly the beginning of her career her single choices for first single almost always are inferior to both the following singles, let alone deep cuts. I am thinking all the way back to how Enchanted and Better than Revenge were far superior to Mine on Speak Now, with future obvious examples being Me!, WANGBT and Shake it off being vastly inferior to their surrounding material? I actually genuinely adore Taylor as an artist but am perplexed why this keeps happening and I genuinely cannot think of an album of hers where this has not occurred (with the exception of maybe Evermore)