Termination ends orientation in toroidal transformer
According to the experience I have here at the company I work for and also some studies I did, if you do not distribute the coils evenly throughout the core, there will be magnetic field inside the toroid, that means that the stray field has increased (ie , there will be more dispersed field, greater inductances and inductive couplings).
Transformers are usually made with concentric windings. When this does not happen, the following is observed:

The transformer ratio can be measured and gives satisfactory results if no load is present in the secondary;
When a load is applied to the secondary, there will be a lot of stray field and, therefore, a lot of voltage drop.