A long long time ago, someone said:
"I think that even though my carrots are okay, I could trade my Uber Cabbages for that other guy's Uber Carrots, and we'd both have variety and Uber Veg."
Well, maybe not, but at least a long time ago, people realised that trade was good. Now, trade costs us something, just like doing the farming, and costs are offset by the benefits of doing the trade.
Years later we are making trade with all sorts of people, and it's great, but... there are some other guys over the river that have cool stuff we can trade, and we can do really well for ourselves if we built a bridge.
So, we built a bridge, a small one, that didn't quite have the capacity to hold all the trade we wanted to do, but we didn't know how much we needed until we got over the bridge...
So we built a better one. Which worked fine, but over that bridge we saw more rivers.
Once we had built bridges for those areas, we found out our first bridge needed to be even bigger and stronger, and also have Toll booths.
You see, we were caught in an never ending cycle of building bridges. Because we didn't know what kind of bridge we needed to build until we'd done a preliminary one, we'd often have to build a new bridge or a better one, and we didn't even know about the other rivers we wanted to
build bridges on until we'd finished building the current bridges.
If we used only the existent bridges, we could plan out our profits and losses really well. We could estimate to within 5% of what everything was going to do. But we hoped that new places, beyond rivers that needed bridging, would provide better profits.
We hoped that doing something that was unknown, untested, unproven, could provide for us a better return than our current simple to understand area of effect because we had previously experienced better returns each time we had built our bridges.
What we forgot was that sometimes the bridges cost so much to build that there wasn't any trade left over to make a good stew. Sometimes you need to live with what you've got. You can quite easily go bankrupt making bridges and forgetting to actually do any trading for carrots.
You can quite easily go bankrupt building new engine technologies and forgetting to actually make any games.