Dear student, All the IIMs usually follow a two-step selection process. First, short-listing on the basis of CAT score and then WAT and PI rounds for the short-listed students.

• Common Admission Test (CAT)
• Written Ability Test (WAT) and Personal Interview (PI)

Most of the IIMs give maximum weightage to Personal Interview and CAT score for admissions. However, factors like academic cut-offs, past academic performance, relevant work experience, gender diversity etc. also play a major role in the final selection.

If you also look at the top Business Schools you will found that the weightage of PI has increased. This is where your past experience matters.

All the best 

Hope this helps