Wayfarer needs to be more transparent with denying POIs. I tried many times and lost faith since no POI got through.. Tbh there were some shots in the dark since i got frustrated with the wayfarer system but most of them were elegible for a good POI.
After years i found a house which has the front of a train build into it. It can be seen from the street and is totally an eyecatcher. With my new found motivation i made an attempt and got declined in record time without any reasoning.. IF I only knew, whats wrong with it i could fix it.. But no.. Nothing.
If the house is a single family private residential property then it does not meet eligibility criteria.
Anything no matter how eye catching and unusual or of historic value on such a property is ineligible.
While the initial submission interface does give little context to what is acceptable, there are tools at your disposal to look into the criteria.
The clarification linked by Eli may show why it was denied, several other clarifications are available in Criteria Clarification Collection - Niantic Wayfarer Community and more knowledge material can be read in Niantic Wayfarer Help pages as well as the Criteria pages. Additionally, each section of the review page has a tooltip (small iās) which can also provide useful guidelines.
Showing the nomination in full may also give more specific, precise advice for your future nomination attempts.
Even if you just look at it from the street? I saw so many murals pokestops which were on private houses or garages. Are they all ineligible POIs?
This is beyond frustrating since it is not really possible to submit a single POI for years now.. And with this architectual unique POI i really thought i had a chance..