C language rock-paper-scissors game (a phenomenon problem where the results are concentrated in two)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

enum RSP_game{Rock, Scissor, Paper, Fail};

int convert_enum(char *input) {
    char *RSP_str[] = {
        "Rock",
        "rock",
        "Rock, paper, scissors"
        "Scissor",
        "scissor",
        "Scissors"
        "Paper",
        "paper",
        "Po"
    };

    int result;

    for (int i = 0; i < 9; i++) {
        result = strcmp(input, RSP_str[i]);
        if (result == 0) {
            if (i == 0 || i == 1 || i == 2)
                return 0;
            else if (i == 3 || i == 4 || i == 5)
                return 1;
            else if (i == 6 || i == 7 || i == 8)
                return 2;
        }
    }

    if (result > 0 || result < 0)
        return 3;
}

int main(void)
{
    char user_input[10];
    enum RSP_game user_choice;
    int computer_choice = 0;

    do {
        computer_choice = rand()%3;
        printf("Choose between scissors, rock, and paper (exit:q):");
        scanf("%s", &user_input);

        if (user_input[0] != 'q') {
            user_choice = convert_enum(user_input);

            if (user_choice == 3) {
                printf ("Value is not valid).\n");
                continue;
            }

            if (user_choice == computer_choice)
                printf ("It's a tie."\n");
            else if (user_choice > computer_choice)
                printf("Won)\n";
            else
                printf("lost"\n");
        }
    } } while (user_input[0] != 'q');

    return 0;
}