why do i have to run "composer dump-autoload" command to make migration work in laravel

i have built some migration classes in my application to create the tables i need , but i keep getting errors when i run the command:

composer dump-autoload

then it works again as expected , am i doing something wrong that generates this error or this is a normal behaviour in migration ?

Below is the error that i get when running the migration process:

  [Symfony\Component\Debug\Exception\FatalErrorException]  
  Class 'CreateVideoStatusTable' not found  

via Chebli Mohamed