going back for a while to Anno 1404

 The peasants need only a bit of fish to eat initially, which is fine given the human nature.

Then as the population increases, their wants also increase. Now, how is this logical you might ask.

I can consider this in light of needs arising due to presence of resources or technologies to extract them.

And once people have a taste of these new goods, it never goes off. It is very clear in the game too that if you take away any of the basic needs once the population has advanced, they get very pissed off quickly and start leaving or raising rebellions.

You feed the hungry lion once, you need to keep feeding. There in lies the challenge in raising huge cities with large populations, surplus stock of all stuff and good control of the multiple islands. If there is also a military goal, significant amount of resources get redirected in that side too.

Most of the time, the supply and smooth running of resources between various islands requires a lot of micro management, until there is enough cash and population to support enough trade ships, large and quick enough raw material productions, huge storage and a large enough set of war ships to protect your shipping lanes. Due to the imbalanced nature of resources and development level in each island ( resulted by our own decisions to direct attention and vision to particular aspects), it takes a few attempts and a few rebellions to get the tempo going.

Now I know that before raising the population for a given level, I need to ensure a strong supply and it is prudent to spend time and pile up materials and ships as required to keep the supply up and running for the expected higher demands.

Combining this with the impromptu missions requiring a variety of resources, one would start expecting production lines to keep every single resources at a level higher than its need. This is practically impossible to achieve because even raw materials which are abundant might often need to be redirected to its next level of production to get a very efficient generation of the higher valued product.

A sudden demand for the underlying raw material might be difficult to satisfy, and one might have to resort to buying for the needs while borrowing from the existing stock or shutting down a few production plants to get the raw materials piled up. 

There is also a risk with shipping products in excess of its use across islands. Ships tend to get filled up with goods that are not needed, and take away slots meant for other critical goods and suddenly you might notice a rebellion and it might be too late to take recovery actions. This is why constantly checking your stockpiles and cargo loads on key shipping lanes helps keeping the lanes healthy.

The fun part of the game is the ability to keep switching between raising the automated systematic shipping lanes and production queues while also doing a tiny bit of exploration, investments in resources and strategically raising population levels, wars etc.