I think about being perfect quite a bit so when I come upon it in the scriptures I like to take note. Reading in Hebrews 11:40 says that "God having provided some better thing for us, that they without us should not be made perfect". In the footnotes the Joseph Smith Jr Translation says "God having provided some better things for them through their sufferings, for without sufferings they could not be made perfect". There is a huge difference wouldn't you say?
This says a lot about the process of attaining perfection and that it is in fact a process, at the same time I believe in any particular moment we may be perfect even as Christ was perfect if we have a humble heart that is willing to follow the promptings of the Holy Ghost and lean not to your own understanding.
The sufferings is what gives us the opportunities to make our choices and decide the path that we will take in our personal spiritual growth. These things will not be forced upon us but must be taken willingly. This is another reason it is a very good idea to be grateful for whatever comes in our lives. It truly is refining and defining us and we have a lot to say about what that means. And make no mistake, we all will have these challenges and sufferings in some form or another and probably in many forms. (physical, social, intellectual, spiritual, relationships, psychologically, etc.)