Submission is where Disney will put you if (on paper) you look like you could fit in, but you don't stand out. This will generally happen after you submit your initial application but before you are given a web-based interview or phone interview opportunity. People can get stuck here because those in submission are basically in limbo - if enough people reject their offers or don't do well later on in the interview process, Disney will take you out of submission, but often times you can sit there until application season ends. Those in submission often will have "neutral" applications, and didn't stand out enough to the computer system Disney uses to filter through applications to automatically move on.
Basically Disney has an automatic system that filters through applications before they bring actual humans into it. So when you submit your initial application, try and include buzzwords. Buzzwords are words that software programs pick up on to choose who "they" think should move on in the application process. This could include Disney's four keys (safety, courtesy, show, and efficiency), guest service or customer service, and using good descriptive words (assisted, maintained, organized, etc.). Just make sure your application reads well! Try put yourself in the mindset of Disney recruiting when you go through your application, if you were hiring based on someone's paper profile, would you hire yourself? You could also have some friends or family look it over before you press submit.
Another way to avoid submission is through role choices. If you know your application centers a lot on photography experience and talks a lot about safety, photopass and attractions would both be good roles to put down. So think of it this way: Disney is looking at your application and pairing your experience and strengths with Disney roles. If you put no interest in those roles, you might get stuck in submission. Keep in mind that many people only put interest in a few roles and move on, but those people have very strong applications. If you know you don't have much experience, you might have better luck listing more roles. Just a thought.
Going off the above paragraph, include as much volunteer and work experience as you can! More experience = better chance of getting through.
I'm going to include helpful links below. A lot of this information I got off of Brittany Earns Her Ears, a super helpful blog so you should go check that out. Some of this is my own understanding of the process, as well as my own experience going through it. I had minimal work experience and a fairly weak application, but I put interest in every single role except housekeeping. I got QSFB, which looking back at doesn't surprise me at all. On my current program (going back and editing to add this in here) I'm in attractions and I put a LOT of emphasis on safety and guest experience on my application which are two essential keys to working in attractions.
http://www.brittanyearnsherears.com/2016/04/spring-2017-application-faq.html
https://disneyprogramsblog.com/disney-college-program-questions-of-confusion-part-4/
https://disneyprogramsblog.com/application-progress-status-bar-information/
I'm posting this picture because this is all I want right now.