As an architecture enthusiast, it is possible that you have come across the following question: where all the models made by architects for clients and competitions go once they serve their purpose?
Perhaps many of them are simply thrown away, some end up in cellars where they begin to rot and fall into pieces until they are no longer recognisable, some of them might be sold or donated to institutions, and others might be well preserved or exhibited somewhere around the studios where they were conceived too.