What potential issues can arise when trying to access array offsets in PHP?

When trying to access array offsets in PHP, potential issues can arise if the offset does not exist in the array. This can result in a notice or warning being displayed, or even an error if error reporting is set to a higher level. To avoid this issue, you can first check if the offset exists in the array before trying to access it using isset() or array_key_exists().

$array = [1, 2, 3, 4];

// Check if offset exists before accessing it
if (isset($array[3])) {
    $value = $array[3];
    echo $value;
} else {
    echo "Offset does not exist in the array.";
}