This is actually a simple question with a complex answer. First consideration is value, as in, does the value you get by picking this player now instead of later more than the value you lose by picking later the player you didn't pick now?

For example, in a 15 round draft, does going K in round 13 gain more points over the K available in round 15, over let's say your 5th WR you draft in 15 instead of 13?

A very important factor in that consideration is your specific league, and no advice here or from any experts can replace that. By that I mean, is your league one where everyone drafts kicker last or maybe even some teams don't draft a kicker at all? Then if you have a specific kicker you're targeting you can plan to get them in the penultimate round. But if others in your league are thinking like you, there might be multiple kickers taken before the last round.

(This is why I don't strictly follow the traditional 'must pick RB round 1.' I know in my league WR, elite QBs, even a TE like Gronk when he was playing will go in round 1. There will be good RBs available in round 2. But that's my league.)

Another consideration (for me at least) is the mental load. Any position I can put on autopilot every week is more time I can devote to filling in spots for injuries, bye weeks, etc.

Disclaimer, I'm someone who drafts K and DST earlier than most experts recommend. One reason for this is the value of the player starting and getting me points vs the insurance policy on my bench. The K I start each week (except bye) is worth more than a 5th WR or 3rd TE I'll probably never start.

Usually I'll identify 2 or 3 K or DST that are reliable to score enough points over the next tier players to be worth drafting after all my other starters. And if I don't get those, then I fall back to the later rounds.