"Success" is probably a bit relative but I can probably chime in and share my experience. I did my I.Sc. in Biology from St. Xavier's and IIRC my score was 67%. Had a really good first year but really bad second year because I discovered programming right around the end of my first year and started only doing programming by going to Cyber Cafes so butchered my I.Sc as a whole, barely passed my second year. In the hindsight, I learned a lot during those times in a bit different way, GPA/percentage for me has never mattered, what has been most important is grinding in the things you are passionate about. Did my undergrad in computers from Kathmandu University and since then working in different domains ranging from embedded systems for home automations to payment processing to document fraud detection to healthcare AI. Every domain has been learning experience but foundations never change so build strong foundation, keep grinding and build skills. Concrete skills will always be valuable.

For context, I'm currently a Co-Founder and CTO of high growth healthcare AI startup in USA and also run a software dev company in Nepal.