From a collection with geospatial index, some requests are not bijective.

Search from A = [48.8547930548148, 2.37725013667164]
db.my_collection.find({loc:{$near:A,$maxDistance:0.000449660802959365}}) returns some results, including this one : B :[48.8547531964291, 2.37711571072754]

Nevertheless, the reciprocity does not return A, worse, it returns nothing :
db.my_collection.find({loc:{$near:B,$maxDistance:0.000449660802959365}})

This last request starts to return some result when increasing the maxDistance, which is not acceptable as a workaround for us.

This issue is relatively frequent : 1 document for 20 does not work correctly.

Reproduced with always some erroneous documents on Debian, Mac OS, and even after re-indexing, dropping database, removing db files.