It has to be a financial or timing thing as nobody is ever going to achieve anything worthwhile or productive in such a short timeframe.A proper timetable needs to be spread out for those who need it,as here in the UK. Remedial classes last for 45 mins and every care is taken to ensure the students are catered for properly.Those that need help the most are the ones who should be taken care of the most.Education is an entitlement, not a privilege.
Too many students to tutor. An effective upper limit to tutoring. If people want more time then they must pay for it.