Why didn't voters in the assemblies have as much power as the magistrates or senate

the legislative level

Explanation:

because each position has a level of power and those with greater power are what the final decisions made, but over time this has been changing according to the needs of the government, since for decision making with greater magnitude, You have to ask for opinions in the field to see if you agree with the law or decisions that are taken, since in the field there are representatives of the different states so your opinion is important since these decisions are applied at the level national and apply through majority vote