3 years into a 6 month project: what scope creep looks like from the inside

my farming game was supposed to take 6 months. it is now year 3. i want to write down how that happened because i genuinely did not notice it while it was happening, and maybe someone reading this is in month 4 right now

month 1 to 6: farming, a small town, 5 crops. the actual game. it was fun and nearly done

then: "it would be cool if there was fishing". fishing took 2 months because fishing needed a minigame, new UI, new items and new save data

then weather. weather needed seasons. seasons needed new crop rules. new crop rules broke the economy so i rebalanced every price. then villagers needed schedules that react to the weather. you see where this is going

none of these features were bad ideas. thats the trap. each one was a good idea on its own and each one touched 4 other systems

things that finally helped:

• a cut list. a doc called "not in 1.0". every new idea goes there first and has to survive 2 weeks before it can come out. most of them die there peacefully
• a vertical slice. one season, fully polished, start to end. it showed me how much work "polished" really is for one season, times four. that number scared me straight
• a public date. i put a demo date on my store page. now theres a real deadline and real people asking about it
• playtesters early. 10 people played the slice and almost nobody used fishing. two months of my life. they wanted more farming, the thing the game was about in month 1

demo is out in a few weeks. if it isnt, you are all allowed to bully me in the comments