Guru Dakshina

Ekalvya's gurudakshina
Upon hearing of the incident, Drona is impressed but also angered. When the young man presents himself to Drona, the guru accepts him but demands his right thumb (which is essential to position an arrow on the bow-string) as gurudakshina. Ekalavya complies, but cripples himself and thereby ruins his abilities as an archer.
According to the Mahābhārata, Drona was fulfilling his dharma to protect the fated superiority of Arjuna. He has been criticized by some scholars for demanding something that was not his due. The deterministic suggestion also points out the contradiction that if Arjuna's superiority was truly fated, Ekalavya's mastery of archery would have no consequence on the destiny of the Pandavas. In Mahabharata, Drona tells his son that education is for everyone and that they cannot close the doors of education on anyone. He claims he took Eklavya's right thumb as he did not get his education in the right way but stole his education by watching Drona teach others.
Others have suggested that Dronacharya suspected Ekalavya learned his skill by secretly observing the training sessions of Arjuna and his brothers. In this scenario, although Drona could have demanded an even greater punishment for covert martial training under the law of the time, he asked only for Ekalavya's right thumb.
Ekalavya has been lauded by many Indians, including Adivasis, as a paragon of achievement who achieved great heights of accomplishment through his own self-initiative, to which the nobles of the Kuru house could only aspire through formal tutelage. Ultimately, however, the Mahābhārata does not settle these moral ambiguities, and leaves the tale open to speculation and discussion. Ekalavya later learned to shoot again using only four fingers and left-handed and was a mighty warrior hailed in several places in the Mahabharata.