What are the potential reasons for the code snippet provided not displaying any output and how can this issue be resolved?

The potential reason for the code snippet not displaying any output could be that the PHP error reporting is turned off, causing any errors to not be displayed. To resolve this issue, we can turn on error reporting by adding the following line at the beginning of the script:

error_reporting(E_ALL);
```

Here is the complete PHP code snippet with error reporting turned on:

```php
<?php
error_reporting(E_ALL);

$number = 10;
echo "The number is: " . $number;
?>