A contract with a bad design

bad.sol

struct Bet {
    address user;
    uint bet;
    bool won;
}
contract Lottery {
    address immutable owner = msg.sender;
    Bet[] bets;
    // store how much each user 
    uint winnings;
    function deposit(uint bet) payable external {
        require(msg.value == 1 ether);
        bets.push(Bet(msg.sender, bet, false));
    }
    function pickWinner() external {
        require(owner == msg.sender);
        uint winning_number = 0;
        uint winners = 0;
        // Imagine some magic code for generating randomness
        // and assigning to the variable winning_number
        for (uint i = 0; i < bets.length; i++) {
            if (bets[i].bet == winning_number) {
                bets[i].won = true;
                winners++;
            }
        }
        winnings = address(this).balance / winners;
    }
    function claim() external {
        // function that allows people to claim
    }

}