Why did the immigration officer say that my last visa extension in Thailand would be my last one?

Hi there! Today I went to MTT and I got my last extension, and I say that I got my last extension because the IO in charge told me that this would be my last one. Furthermore, they asked for a return flight receipt, which is something that I felt they might ask for. They gave me 60 days, even if I told them that my flight would depart on March 21st.

Apart from that, nothing else to report.

Regards,

Enrique.