Unlike its peers, Tech Mahindra has relied heavily on telecom clients to boost revenue. That will change as Joshi tries to take advantage of his own expertise and experience dealing with financial services firms to turn the company around. "BFSI is the single largest spender from a tech services perspective. It's very important for us to play aggressively in this space. Large banks typically spend over $10 billion a year in terms of technology," Joshi said.