I have had quite a lot of experience with this in the UK, so I can only share my own observations and experiences.
For me there are a couple of career advantages to getting selected for open call art exhibitions.
Firstly its about being current, you are making work that is being selected, people are seeing it and you can show on your cv that the stuff you are making and showing is actually in demand by contemporary galleries and curators.
Second, There is the chance of actually selling your work during the exhibition.
This painting was selected and hung in the Royal Ulster Academy 2021 show and sold for £1000, I got £700 after commission but not only is it a boost to my bank account and income, it is also validation that not only artists, gallerists and curators like your work, but also the person in the street.
Thirdly there is always the small chance that you may win a prize.
This painting was selected for the Bath Society of Artists show in 2021 and subsequently won the Bradford gallery Figurative prize. It was £250 and also sold for £300.
Unfortunately it is highly unlikely that a painting will win, but always possible.
The fourth reason why you may want to enter competitions is that it is a part of the lifestyle of an active artist and gets you into the opening events of the exhibitions where you can make contacts and meet people. The art world, unfortunately, is still a place where people recognise names and will want to work with those people they know rather than strangers. when someone sees your work and likes it, they may not have a place for you in their gallery or their current show, but opportunities may arise in the future and your name will pop into their head if your work fits and they liked it.
The final reason for entering open calls, is that if you are selected for several years by a prestigious academy or art society they may offer you to become a member. This will allow you to have the abbreviated letters after your name for example: RA, RWA, RCA etc. This will do wonders for your career and give you a provenance that will possibly enable you to make a good living at being an artist.
I will continue this discussion in my next blog post.