I've anonimised this as much as possible - no names, no location - but here's a horror story of poor airmanship by two aeroplanes and one of our own.While I was waiting for a customer's arrival I sat in the tower observing arriving traffic and listening to their radio calls. My customer (in a gyro) called for joining instructions and, shortly after, announced he was joining left base, visual with two fixed wing aircraft ahead.To my horror, the first aeroplane initiated an orbit on final approach. His propellor was still turning and he hadn't announced a fuel emergency so I don't know why he didn't go around to avoid the occupied runway.As I looked between runway and orbiting aeroplane, I noticed the second aeroplane had also started to orbit, at the point he would have been turning final. Luckily there was sufficient horizontal and vertical separation between these aircraft otherwise debris might have been strewn over a wide area.The first "orbiter" landed and promptly vacated. The second "orbiter" landed and, ignoring the radio controller's request to vacate, did a 180 on the runway and started backtracking from 500m along the runway.The gyro was now on short final, facing a backtracking aeroplane.The radio controller again requested the backtracking aeroplane vacate onto the grass and he turned 90-degrees to comply.The gyro landed before the aeroplane had vacated - plenty of horizontal separation but the runway was still occupied.The two aeroplanes, above, were both radio-equipped and knew of other traffic behind them but endangered themselves and those on the ground by orbiting rather than going around.The gyro was also radio-equipped but was confident he'd land well short of the vacating aeroplane and wouldn't be endangering himself or the other aircraft on the occupied runway.Orbits are an excellent method of distancing yourself from other traffic, performing a 360-lookout, re-orientating yourself or generally having a nose-around. But they must not be used in the circuit.We use ears, eyes and brain to form a mental picture of circuit traffic ahead of- and behind us. Based on this situational awareness, we plan ahead to ensure separation. If any distancing is required it's achieved by extending downwind or going around.And, of course, every approach is a go-around, unless all the stars align allowing us to land.