What could happen if I don't put a `require Module` code in a BEGIN block?

Question

Is there anything wrong with not putting the conditional module loading in a BEGIN block? Without the BEGIN block changing the environment variable after precompilation would still affect which module is loaded.

my $table;
#BEGIN {
if %*ENV<TABLE_A> {
    require MY_TABLE_A <&get_table>;
    $table = get_table();
}
else {
    require MY_TABLE_B <&get_table>;
    $table = get_width();
}
#}