Totally agree. I’ve been lucky to get into OneZero twice and I don’t know if I did anything that anyone else doesn’t do…I got lucky. Luck is a huge factor and bigger than anything, and if you can get one the next one is easier because you have at least a relationship with an editor and a little bit of name recognition.
Other than that, I think it’s about writing about something you have a unique perspective of or a personal connection to. Even with OneZero, I got an article in about a scooter accident I had that got traction and the contractor/employee debate with Uber/Lyft drivers as a driver. Worked at Walmart? Write about that. Worked at McDonalds? Write about that. Try to write something that no one else can write is my biggest suggestion to maximize luck.