Enterprise Mobility Car Washer/Detailer interview questions

1st round of Telephonic interview with general questions about my work status availability etc. Followed by an in-person interview at a different location than to what I applied for. 2nd round of in-person interviews for the Car Washer position with questions about my retail-oriented experience, customer service, etc. All went well, only to receive a rejection in the end. Which is not the problem unless the HR tells the reason for rejection. They didn't. Despite being a good candidate for a well-rounded knowledge of automobiles. The whole process lasted over 4 weeks from application to rejection with 2 rounds of interviews and a trip to a different location.