Hi there,
Short answer? Absolutely! Longer answer: start up experience, generally speaking, is viewed very positively by admissions committees. If the business is/was successful, great! If it wasn't, if you can articulate what you learned and why it failed, that can be just as impactful. Success of the venture is a small part of the story.
The reason why adcoms love this type of experience is it gives them insight into your character while at the same time giving them a potential student that will bring some very diverse and exciting experiences to the classroom.
The trick becomes how do you communicate these experiences? How do you convey what you learned and where it will take you next? How do you share your experiences, long hours, and dedication? How your start up experiences are viewed is completely contingent upon application execution.
It has the makings of powerful story and gives you a rich set of experiences to pull from to show adcoms exactly what you're made of. Not to mention, it helps you stand out from the thousands of Finance, Consultants, and IT professionals applying!
If you have any questions - I'm happy to answer them!
Bhavik