I was building a custom form for my client where I wanted to create a shortcode that generates a button where a user could add a Subscription to their cart.
Each subscription product has a number of variations. Variations are stored as posts but meta information is stored as if they are product options.
If you try to retrieve the post_title of a variation by its ID, it will display something like the following.
Variation #0000 of Some Product
Here is how to retrieve the product option title rather than the variation post title.
// Assuming you already have $variation_id set get_post_meta($variation_id, 'attribute_options');
Returns an array
[attribute_options] => Array (  => Some Variation Title )