Multiple IRR

Can anybody explain me in detail about MIRR ? I have read from CFAI as well Sch too but could not get through. thx

Multiple IRRs occur when their are negative cash flows. Example. Initial cost $5000 Period 1 - -$200 Period 2 - $8,000 Since there is a sign change, two IRR’s will be present.

MIRR occurs SOMETIMES when there are multiple sign changes (more than one sign change). It is not guaranteed to have a MIRR or no IRR if there are multiple sign changes though.

Another explanation is that Draw NPV profile. If the profile intersects discount rate (horizontal axis) more than once, you have multiple IRR. If it does intersect horizontal axis then there is no IRR

Which is why NPV is superior when ranking pjts.