Speaking of players being "cut" each year, I did some research and looked at the WNBA draft class of 2013. This class included notables Brittany Griner, Elena Delle Donne and Skylar Diggins. That was 5 seasons ago. Of the 36 players that were drafted, only 13 are still active.
1st round = 9 still active
2nd rd = 3
3rd rd = 1
With the influx of new talent coming into the league each year, rosters are turning over faster than ever.
As of today 5/15/18 - 2 first round players from last year's draft are no longer active. Evelyn Akhator (3rd over all by Dallas) and Tori Jankoska (9th over all by Chicago).