Why is issuing security tokens on a vanilla ERC-20 token standard restrictive for STOs?

Here are some limitations with vanilla ERC-20 Tokens:

• Since the distribution is not automated, ventures sharing profits to the holders is not possible.
• Once the tokens are issued, they become freely transferable, taking away transfer restriction and jeopardising the security behind who transfers tokens and who receives payment.
• There is no way to check the information of the token holder.
• ERC-20 Tokens do not support KYC/ AML compliance and do not provide allow for the extraction of token holder lists.