For the 15 years or so that I have been involved in the IT industry, the most stable technology around has been relational databases. A SQL Server database created more than 10 years, if modeled properly, is just as good today.
The same cannot be said about most other technologies. Front end technologies for instance, moves faster than ever. Any front end code written today is most likely to be rewritten within a few years time.
An important success factor in a project is to have as few moving, unstable parts as possible. Relational databases have been around for decades with a good track record, while most NOSQL databases on the market are new and immature. I would thus think twice before deciding to use a NOSQL database.