This idea that grinding ranked = working hard is false. Lets use a proper example of a successful team. Remember Astralis in CSGO? 4 time Major winners. Well newsflash but Astralis players almost never played Faceit Pro League (FPL).
They did their aim routines in aim maps, played bunch of dms for hours and scrimmed. That's all they did for 2-3 years and became the ultimate dynasty in CS history.
Ranked games aren't everything. If you have enough experience playing the maps then all you need is good aim practice, strats and scrims to remain at the top level, also ranked creates bad habits and complacency which is rarely seen vs other pro teams and so some people find it less enjoyable.
TLDR: Scrimming is the most important measure of how well teams prepare not the number of ranked games people grind per day.