Humans make up some incredible things and then they forget that they made them up and then think they are real and fixed, instead of not real and totally changeable. Part of what we make up is "about" something else that we also made up - kind of a made up about a made up - such as "how awful it is" and how it will threaten the person in some way. The "awfulizing" is unnecessary and causes suffering and struggle that is not inherent in what happens. We also totally misestimate the size of the impact of a future event (undesired outcomes) and greatly underestimate how well we will cope with it. 95-99% of 'feeling bad' is strictly caused by "made ups", which do not need to be there and which do not exist in reality "out there" - just in our heads. (See What Is A Story And What Is Not A Story for a full discussion.)
And then they don't revisit or examine those to see if they should be revised and/or replaced to fit with the truth.
This is true with the subjects of this piece.
If you hadn't gone to the gym or ever lifted weights or exercised your muscles in some way, would you consider yourself as having a permanent weakness of your muscles?
"That would be preposterous" might be your answer.
Well, I say it is preposterous across all weaknesses. You just have chosen not to exercise the muscle because you chose to do something else instead.
We get busy with other priorities, so we don't strengthen this muscle
As humans we have needs which we must prioritize to fill and we have things to do and battles to fight and problems to solve. Although we could learn to prioritize, we simply are prioritizing what seems to have priority at the time and not doing something else with a lower priority. (I would propose, however, that you get rid of the weakness you have in prioritizing.)
Many of us have had more "dragons" (negative stories and beliefs) to fight, either from lack of proper training and being fed false beliefs and/or from actual circumstances requiring handling. Those took time - we are not "at fault" for them, as there was no ability in us to handle such things better - or to disappear them. It just took time - that's all. No foul, no fault...
What a real weakness is, but where it must be accepted
A real weakness would be not having a brain or having extreme brain impairment. If either is the case for you, you wouldn't be reading this. So you have no real weakness that matters. Note that there might be undesirable conditions or circumstances, but those are not indicative of weaknesses that would determine the quality of your life or which would keep you stuck where you can't do anything about life. (I Am Whole And Complete.)
"Right now, at this very moment, we have a mind, which is all the basic equipment we need to achieve complete happiness."
The Dalai Lama in The Art Of Happiness.
If you can't use your arms and legs, that might be unfortunate and something where you can never be strong in, but it is not a "bad" weakness or one that limits you from achieving a good life. It will, of course, limit you from doing some things, such as running a marathon, but not from anything that is of great importance. Note Stephen Hawking or W. Mitchell or the others included in Bad Past, Good Life - where they created a good life despite circumstances and conditions.
Otherwise, a weakness is simply...
A weakness is simply something that hasn't been developed (or strengthened). It is just an indication of something you haven't yet done. It simply represents a potential that has not yet been harvested, for whatever reason - a bad start in life, other priorities, not yet knowing how to manage life, and just not knowing something yet that could have you strengthen it. Of course, because of limited time, we have to leave many areas of potential unharvested - and one cannot simply label those as "faults" or weaknesses, because it is simply something we chose not to develop yet.
And we don't need to be hugely strong or strong in a large number of areas, just in areas that affect our happiness skill set, which is independent of circumstances and/or weaknesses in other areas. (Be clear on "How Much Is Enough?")
= "lacking strength, not functionally effective in the area of weakness"
That's the definition, but we don't have to have weakness be regarded as "bad".
It is simply a missing. And, if we have time, most of us could solve a weakness by learning and devoting attention to developing the functionality. Anybody, if he/she has the time, he or she can definitely "solve" a weakness and fill the whole.
The skill and knowledge you must learn (and that pushes you over the "tipping point"), as "the top priority", is the way to think about life and its contents, especially being able to see the "illusions" (made-ups) that are not real and seeing that there is no justification for criticizing oneself nor of fearing the future or a "fault". It starts in nailing your Life Philosophy from reading in the Philosophy and Psychology areas on this site. Follow the learning plans in those sections and/or scan the detailed contents sections to spot what you need to learn more about - and then read them - right there, right then or as soon as possible.