I am looking for a phrase (can be multiple words) to describe following situation:
Even if you do not like to do something, and try to avoid doing it, circumstances would keep repeating until you will learn how to deal with it, and accept it.
In my native language we have saying "Odriekaneho chleba hruby krajec", literal translation is "from the bread you do not like, (life) will keep giving you a thick wedge as long as you keep refusing it".
In real life: junior automated test developer (not assertive enough) is afraid (again) to ask senior developer for some changes (again) in the code which will make writing tests easier. Developer knows how it should be done, but keeps not doing it because it saves him some time, and it was agreed to make the changes. There is no good workaround, and junior needs to learn how to be assertive and request adding such agreed-upon hooks.
I am not looking for a workplace-related solution (I know it), but for a phrase to describe such situation.
I found necessary evil, is there something else? With the meaning that it will keep repeating, and in the end it is good for you to master it.
Edit: Answers so far have dark, negative connotations: "uphill task (battle)", "necessary evil", "bitter pill". I was hoping something more positive, almost karmic associations. Maybe it does not exist... :-(