Look in the decisions tab at the Government values decision; if you mouse over the button to take the decision it will read out a number of values including Required Governance and Current Governance; Current governance is based on admin tech and meritocracy; meritocracy grows over time based on corruption level (the in-game encyclopedia has the formula). Required governance is based on the number of provinces you have, their development, their autonomy and the land ownership/serfdom situation in the provinces.

The inefficient bureaucracy modifier triggers when current governance falls below required governance; usually the fastest way to correct that is to boost autonomy in some provinces and the next calculation cycle should push your required governance down below the threshhold.

What nation and situation did you run into this in? We've tried to benchmark it such that it only limits your ability to simply take all land everywhere for the crown when conquering though I've occasionally run into it restoring Byzantium simply because of the speed at which one can reclaim those cores in the early game.

I played as baluchistan in an attempt to form the Mughal Empire, the year is 1360 and I had been building up money and time waiting for the muzaffarids to be at war and then they did and I took 5 provinces and was unable to core them. https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=1482730054 My required governance is 3.2 while my current governance is over 22.

I've tried playing as several nations since then and in all cases my governance is way above the required and yet I still can't core anything because of inefficient bureaucracy it's really annoying.

引用自 Truth：

I've tried playing as several nations since then and in all cases my governance is way above the required and yet I still can't core anything because of inefficient bureaucracy it's really annoying.

Are you sure it's not because of separatism? Territorial cores cannot be established until separatism dies off. Also note that values have been changed for provinces such that not being a core no longer makes the province almost inherently worthless.

I mean the instant I conquer them I cannot core them, I don't mean after making them states.

引用自 Truth：

I mean the instant I conquer them I cannot core them, I don't mean after making them states.

I know what you mean, and I am saying that the initial cores (called territorial cores by the engine) following conquest are only possible after the province has no more separatism.