An overwhelming majority of Indian students who travel to the US for higher education belong to the STEM category. For the annual H1B quota of 20,000 visas reserved for this category, about 30,000 applications are usually received. On the other hand, against 65,000 H1B visas allocated for non-STEM applicants, three to four times that number apply.
Therefore, an applicant for an H1B visa from the STEM category invariably stands a much better chance. That is why several students from the non-STEM category, even if they find a job in the US after graduating, have to leave for their country of origin as they fail to acquire an H1B visa. Another factor that works in favour of STEM students is that their OTP is valid for 36 months, which entitles them to three attempts at seeking the coveted H1B visa.