Including wp-load.php in custom .php file causes page processing to stop. Why ?

Solution:

I think the problem is with wp_load.php or maybe you haven’t read the wp_load.php file correctly.

Wp_load always requires wp_config.php If it doesn’t get it it will die with an error. See the below code in wp_load.php file

$die  = __( "There doesn't seem to be a <code>wp-config.php</code> file. I need this before we can get started." ) . '</p>';

With some more identical code like this and error associated with it.

so when you require_once ‘wp_load.php’ and It doesn’t get wp_config.php It will die and stop the execution and you won’t get any further print statement

Hope it clarifies you.