TRE talking here.
The most frequent problem that one sees as an examiner with circling approaches going to pot is due to not enough evaluation of the wind effect, particularly during the turn to base/final.
Modern FMC, electronic flight display equiiped aircaraft give you a track line and precise groundspeed information.
Always, terrain/circling requirements permitting try to arrange your turn to base and then finals to be INTO WIND. The reduction in groundspeed will prove a huge benefit, making for more time to assess the flight path, turn rate required. ROD etc.
Rubik 101 touched on this in his post.
If you can't make the turn into wind, then being able to anticipate the demands of your base turn/final flap extension/turn rate/ROD selection will help no end.
Make it a part of your briefing, and in briefing make sure PM knows what you are thinking. If it should mean that to position the aeroplane for a base turn into wind, the runway is on PM's side of the cockpit, make sure PM knows you want him to include it in his scan, and advise you how you are doing, passing the threshold etc.
Also, if there is an apprecaible headwind on base leg, it will skew the nose towards the runway, thus helping you as PF to enjoy a view of the runway, final approach etc.
Somebody commented " how can you fail? It is not a test item" There is not enough here to know why the examiner said no-go. There may have been other items not done correctly. It may have been an operators check that was failed, not a licence check. In most companies one expects the operators standards to be higher then the authorities.
Try this one on for size though. If someone flies a non-precision, or a circling approach, and the aeroplane is put in a position from which it is impossible to land SAFELY, the examiner will breathe a sigh of relief if a go-around is flown and reversion to plan B takes place. You do have a plan B of course!
Take a look at Alicante runway 28, the VOR/DME approach. It has an offset of 20 degrees from the runway heading.
You could fly that approach perfectly, break out at minima, and be unable to manouver the aeroplane into position for a landing without seriously destabilising the approach with say a crosswind from the left. A go-around and diversion would be cool, throwing it on the ground in an untidy heap would not. If you don't have the fuel to go-around and proceed with plan B, then perhaps plan A was lousy!
Hope that helps,
BSD.