Prashant Kishor, India's top political consultant, has told BBC Hindi that he didn't join the country's main opposition Congress party due to a disagreement over the implementation of a revival plan proposed by him.
Mr Kishor had been invited to present a strategy to help the Congress revive its political fortunes ahead of the national election in 2024.
"The leadership assessed the blueprint we prepared carefully and agreed that it was good for the party. But we differed on ways to implement it," he said.
Mr Kishor was also asked to join the Empowered Action Group (EAG), a new decision-making body set up by the Congress. But after days of public speculation, he turned down the offer, tweeting: "In my humble opinion, more than me the party needs leadership and collective will to fix the deep-rooted structural problems through transformational reforms."
The refusal was also partly due to the party's "problematic" decision to form the EAG, he said.
"The group did not have any constitutional propriety and all the members were nominated. I found this to be problematic because this new body wasn't aligned with the party's constitution and would have led to a contradiction in the future," he said.
Mr Kishor said that before his refusal, he and the party had "held discussions in a structured way" and agreed on a strategy.
"My blueprint was all about how the Congress should regain its glory days - it wasn't about winning one or two elections. It was to help the Congress resurrect itself as a strong political force in the country," he said.
The Congress has been struggling to regain lost ground since first losing to the Narendra Modi-led Bharatiya Janata Party (BJP) in 2014. Since then, it lost the 2019 general elections and also suffered a spate of defeats in several state elections. It won some states but this was largely due to local leaders putting up spirited fights on the ground.
Mr Kishor has often been credited with helping parties across political divides win elections. He worked in health activism for years before joining Mr Modi, then chief minister of Gujarat state, as a policy adviser in 2010.
He shot to national attention in 2014 when he managed a highly successful election campaign for Mr Modi, using social media and innovative campaign strategies to turn the politician into a brand.
Mr Kishor fell out with the BJP and then went on to help several opposition parties, including the Aam Aadmi Party (AAP) and the Trinamool Congress, win state elections.
Known as the "kingmaker", he has a reputation for picking the winning side - though his aura was tarnished a little in 2017 when his association with the Congress ended with resounding defeats in Uttar Pradesh and Uttarakhand.
While his clients have mostly been successful, Mr Kishor himself has had a tumultuous stint in politics - he was expelled from the regional Janata Dal (United) in 2020 after disagreeing with the party's stand on a controversial citizenship law.
If he had joined the Congress, it would have been a shot in the arm for the Gandhi family, which has led the party for decades.
But even the speculation over whether Mr Kishor would join or not was shadowed by a controversy over his consultancy firm, the Indian Political Action Committee (I-PAC), signing on the ruling Telangana Rashtra Samithi for upcoming state elections - where it would directly take on the Congress.
Mr Kishor also said that while the BJP would remain strong over several decades, they weren't invincible.
"A strong Congress is important for India and I still wish them well and I hope they implement the strategy they agreed on," he said.