SHARPEN OR LOOKING FOR SOMETHING ELSE ?

Always I have believed so far that perfection it's a total waste of time , that mean if you are able to do a thing in very good way , it's better that you shift your focus on try to learn something of new instead of struggle to improve it.
Let make a example , if you start to learn english, in the first years you learn about 60% of the words , in the further two or three years you will learn about 80% , hereafter it's a matter of sharpen , and could take three or four  years in order to add a 5% , so , after  twelve years you will reach 100% , that mean a perfect english , it's worth spend so much time only for sharpen a thing ?
Well , if somebody had asked me this one years ago , my answer would been " no " , definitely , if you ask me that now , I will answer  " depend ",  if you like  more of one foreign language , I think it's the great thing that you can do  because it's much better speak enough well in different language then speak perfect in one , because this , some months ago I left for a bit my english for starting something  of new , I tryed Spanish , Russian , French , German and  Japanise , all interesting language , was awesome at beginning because in this stage you learn fast , but then I discovered that for the moment I was not interesting about learn these language , maybe in the future the things could change , but at that time I felt that was not necessary  learn them , then I returned on my english and I started to refine it.
The point is this , it's true that it's better be able to speak  enough well in various languages then speak perfect in only one , but  unquestionably is also true that it's better sharpen what you like, rather start something of new but that you are not so interesting about it, at least at the moment.
In short , you should do what you like to do.