Also, when a bid is made to a club it's generally accepted that the talks are to be held with the two clubs alone. However, making it public is essentially the would-be selling club leaking all information about that transfer to the public. For the buying club, it's a betrayal of trust and lowers the likelihood of them attempting to do business with you in the future (negative relationship modifier between the managers involved), for the selling club it increases the likelihood of other clubs putting in offers if there are multiple interested as they now see exactly how another club made their transfer bid.