Purpose behind redistricting and quo bono?

Are the people changing the district map for the general benefit of the state's residents or is it being done for political bias? Do the people who are changing the map have in-depth knowledge of the inhabitants, history and culture within each district to ensure that changes will not result in friction and discord or be unfair to other districts? I should think that redistricting is being done for the benefit of politicians and not the residents and there must be a better way forward. There are so many solutions and examples of basic systems which work well in other countries, which we ignore and try to "re-imagine", instead of just looking around to see what already works fine outside the US and copy it. Probably why the US is near the bottom of all countries in terms of education and at the top of money spent on education vs. the failure of the results. We could certainly use some government leadership by people who actually want to improve the state rather than serve for personal ego and financial advancement. Do your damn jobs.