A few things contributed to me becoming BTC only:

• Learning the difference between the Bitcoin fair launch and the Altcoin Premines
• Learning the difference between Distributed Proof of Work Mining & Proof of Stake
• Reading about the Blocksize Wars and contrasting with the DAO Hack.
• Reading "Only the Strong Survive" by Allen Farrington & Big Al, which helped me work out that everything on the Altcoin chains is vapourware.
  Among other things.
  Peace.