Wow, very nice answers above, which have hardly any truth. Isro cant be like NASA. Understand the technology difference. Our satellite components and materials like - Battery, Hi-rel components, solar panels, gold film shield, navigation sensors, RF & Microwave which builds transponders -- everything is imported and majority from the USA. They may not all be invented by the USA, but definitely not by India. So, u can say that 80% spares are imported. Now, space launch vehicle (SLV) - components and materials like Apogee motors, Aluminum alloy rigs AA2014, ALuminum alloys (aerospace grade), inertial sensor calibration systems, Wire and ropes (aerospace quality), Screws and fasteners, Chemicals, Cryogenic Motors -- Everything imported.
We are struggling to explore the moon, unmanned..where as, we all know NASA did it long ago with man. They had skylab and they have Hubble, they have SPirit & opportunity on Mars, they have tracked all planets...so more budget just will not work. The purpose of Isro and NASA is different. Isro is for satellite launching which works for India's immediate need and we are adopting readily available and proven technology for the purpose, which need not to be redefined. Where as, NASA is only exploration....So, no comparison of Isro and NASA please