When I "Object > Transform > Flip" an object it doesn't flip in place. Why?

Dear all,

I am learning InDesign for the first time.

I have just imported an image and would like to flip it horizontally. 

When I select it via the content grabber or select the frame (same result) and then go to Object > Transform > Flip (Horizontally / Vertically) the image is not flipped in place but placed next to the frame (or the frame is placed next to where it originally was). 

I have attached a video of what I am seeing.

Could someone help me understand:

a) why this is happening and b) how to get what I need, i.e., the picture flips inside of the frame...

Thanks