Ok,
Example (might be more than one.. I have done some repair work here in 'Central' so I'm not too worried by it .. but something to watch out for)
Way: 229029020 This changeset (dated 6/26/19) add the tags for it to be a platform.

Pre-existing Relation: Platform 8 (6015394) established 2/29/16 already tagged as a platform. Thus a duplication.

Simply:

Multipolygon relations out ways cannot can not share segments.

Relation deleted again.

And another one

relation/14929799

See changeset/129312998 ...

Not fixed. Still wrong.

See https://tools.geofabrik.de/osmi/?view=areas&lon=144.90381&lat=-38.35660&zoom=19&baselayer=Geofabrik%20Standard&overlays=duplicate_node%2Csingle_node_in_way%2Cduplicate_segment%2Cway_in_multiple_rings%2Cintersection%2Cintersecting_segments%2Cring_not_closed%2Ctouching_rings%2Crole_should_be_inner%2Crole_should_be_outer%2Cinner_with_same_tags%2Cways%2Cduplicate_node%2Csingle_node_in_way%2Cduplicate_segment%2Cway_in_multiple_rings%2Cintersection%2Cintersecting_segments%2Cring_not_closed%2Ctouching_rings%2Crole_should_be_inner%2Crole_should_be_outer%2Cinner_with_same_tags%2Cways

The same error as before. Are you even getting these messages?

Outer ways of multipoygons can not share segments!

Not the only place the OSM wiki is confusing!

My 'best' diary entry .. I think ...
@Warin61/diary/45106

Hi,
Welcome to OSM!

A couple of hints?
The multipolygon relation/14934548 (see relation/14934548#map=18/-33.73050/150.98311+ outer ways share segments - they over lap one another, this is an error. Looking at the imagery it does not look like they connect at all .. so 2 simple closed ways would do, no relation required. If they did touch along that segment then .. why have the segment at all? A simple single closed way around the whole single building would do - again no relation required.

Are you local to this building? Do you know if they are joined? In any case I leave you to fix this error.

Other than ferries and pleasure craft there would be no major sea going traffic in this area... darling harbour is no longer a 'working wharf' area.
HMS Belfast renders well on https://map.openseamap.org/?zoom=17&lat=-36.83445&lon=174.79524&layers=BFTFFFFFFTF0TFFFFFFFFF ... don't think anyone would run it to it .. much like a pier. No ferries berth on HMS Belfast, nor on the Australian National Maritime Marine Museum ships.

relation/14877744 diamond creek res - error 'shares segments'... just like the above.

I'll leave it a week and see if you have made any attempt at fixing it.

My understanding of the word 'hulk' looks to be 'different' from others .. :(

However .. I looked at London HMS Belfast and used the same tags they use - more mappers in London ..so that should be 'better'?

I have retagged it along the same lines as HMS Belfast in London, thinking there are far more people looking at those tags.
I would think that it would go into dry dock occasionally for hull maintenance. Probably Garden Island. Onslow .. would have gone to Co-dock. Endeavour dose the occasional jaunt.

HMAS Vampire is NOT a hulk.

Have to wait and see if I got it right ... probably more work to do here...

Hi,
An overlooked something, I think.

The platform Way: 739706579 still has the tag "construction"="steps"

Umm Would that not be finished by now? And why is the entire platform tagged as steps???

HI,
The JOSM validator says level should be integer or at most 0.5 step values .. yet you have 0.7 on node/6015385 ??? And on node 6015385 0.3 and 0.7 ...

You have tagged the outer way of a platform as a platform. That would be ok if it were not part of a relation that tags it as a platform as well ... duplicated tagging leads to confusion.

No reason to use a relation for these kind of things, just tag each landuse and be done.
If they had a common thing like a name then that would be a different case, if it had no holes in it then a simple single way would be enough, no need for a relation?

Good luck.

Hi
The multipoygon relation 14920744 is in error. The outer ways cannot share segments.

I note that the railway area is not mapped at either side. Might be simplest to delete it.

relation/14885858 deleted .. No 4 of the same error...

relation deleted - same error as last 2 deletions...

relation/14920117 deleted. Same problem as last relation of yours I just deleted. You will keep on making the same error untill you realize the error.