General Studies Integrated Course is very important and needed by the students. This course contains a complete package for General Studies in Civil Services examination i.e. it covers a total of 1525 marks out of 2025 marks (GS=1000 + Essay=250 + Interview=275 marks). The 500 marks for the optional course are not included in this.
The idea around this GS integrated course is that, students prefer to complete their General Studies first, and then for final touches go for the optional subject. There are four logics behind it:

(a) The students usually prefer the optional subject as the one in which they have interest or they already had it in their graduation, so that it becomes easier for them to score in it. So, they focus most on General Studies.

(b) With an exposure to general studies they have better option to decide which optional subject they want to choose.

(c) The students preparing for UPSC, do not get time for any other class. They are fully into their courses, regular mock tests and more. Therefore an integrated GS course works the best, because it gets included in their daily schedule.

(d) Finally, General Studies plays a major role in getting selected, after all, it contains 1525 marks (i.e.75%); ignoring the entire general studies can cost a person, their confidence, and selection, both.

Sensibly also, it’s better to complete the basic of civil services’ GS syllabus with all it’s in depth studies and then optional subject becomes easier to cover. Either the students should choose between graduation subject or go for any of the humanities subject (somewhat candidates are exposed to it and have developed basic concepts during their study to general studies courses)