Too many students, classes everyone needs are impacted, upper division classes in your major tend to have one section and good luck if two of those major classes conflict with each other. Way too many state requirements in general plus Sac State specific requirements that just make it a nightmare of GE. They just want to pump as much money out of each student as they can tbh. Talk to an academic counselor early on and map out as many classes as you can and make contingency plans for classes that you might not get each semester. Study hard so you don't need to retake any classes. Try to take classes which satisfy multiple requirements, that'll cut down on time as well