One of the major drawing points within Bioshock Infinite is the design of its characters and the attachment that the game calls on the player in regards to Elizabeth. The way your own character Booker De Witt and Elizabeth communicate and push their way through the story becomes a form of motivation for the player and in a sense is part of why the game had such a strong reception. The view point for most game players actually got drawn from these characters and the ideas explored which prompted further development to the players own connection. Throughout the story you grown to care more and more about Elizabeth and that is what made the story so interesting, however the point of this was just how much of a different game Bioshock Infinite was going to be.
When Bioshock Infinite first started development the people at Irrational Games originally planned to have Elizabeth as a mute character, this mostly came down to a lack of confidence in there own ability in creating a companion character that spoke, their main concern revolved around the player getting annoyed by all the chatter or repetitive quips. However they then played with the idea of this and found having to commonly face the camera towards her so she could communicate would also annoy the player as it would visually interrupt the experience. They then had to be faced with the decision to remove the character or commit to a speaking character. During development this was very controversial around the studio.
Easy enough to say Irrational Games made the right decision in the end as it created one of the most memorable and most amazing games ever made as well as one of the best companion characters who you grow to care about as much as Ellie from the Last of Us.