Openlayers 3 polygon not rendering on map

Question

I've set up a small example of an OpenLayers 3 map, and I am trying to add a custom polygon to the map. If I use the data from the example, it works correctly, the polygon renders, and it is shown on the map, but when I try to add another custom polygon, it is not showing up on the map at all. Here's the code I use:

function initMap(map) {

 var IMap=new Map(map, [50.5973695, 6.200000]);
 var polygons=jQuery("#"+map).data('polygons');
 console.log(polygons);
 jQuery.each(polygons, function(index, value) {
     IMap.addPolygon(index, value);
 });

 IMap.addPolygon('test', [[-12.55,-21.12], [-44,-55], [-88,75]]);
}

Function Map works correctly, as the map is rendered, and centered to the specific position. Function addPolygon also works, because the polygon which I add manually with the IMap.addPolygon line renders on the map. Here is the Map::addPolygon function:

Map.prototype.addPolygon = function(name, coordinates) {

 var _coordinates=[], i;
 for (i=0; i<coordinates.length ;i++ ) {
     console.log(coordinates[i]);
     _coordinates.push(ol.proj.transform(coordinates[i], 'EPSG:4326', 'EPSG:3857'));
 }

 console.log("Creating polygon", _coordinates);
 var Polygon = new ol.geom.Polygon([_coordinates]);
 var feature = new ol.Feature({
     name: name,
     geometry: Polygon
 });
 this.polygons.push(feature);

 feature.setStyle(polyStyle);

 this.vectorSource.addFeature(feature);
}

Here is the two _coordinates which is logged out:

This one is for the dynamicaly creted polygon, which is not rendering:
Creating polygon Array [ Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], 9 more… ]
Inner array example from above array: Array [ 50.5982266, 6.2467439 ]

This one is for the manually added polygon, which renders correclty:
Creating polygon Array [ Array[2], Array[2], Array[2] ]
Inner array example from above array: Array [ -13.12, -21.76 ]

What could be the problem?

NOTE: This question was also posted on stackoverflow.com.