History is littered with stories of investors who collude with others to phase out the original owner of a business. Arsenal Football Club used to be owned by a couple of dudes. Stan Kroenke offered the other dudes money they couldn't reject and they all sold him their shares. Now he has controlling stake and the football club is toiling under his ownership.That is good to protect your control of the business. No matter how many investors you have but you need to maintain the majority shares of the ownership otherwise you may lose the business entirely.
No matter the desperation for investor's money they should never have more than 39%.