In competitive environment a professional should focus on his Strengths or his Weakness?

Weakness, Focus on your weakness to strengthen it. Thia will benefits you and boost your career once you improved it.

both, but focus more on the weakness to make it elevated to strength.

he need to keep and upgrade the strength points and work harder on the weakness point ,

because weaknesses will effect  and harm the strength he has.

Yes a professional should focus on his strengths, weakness, threats and opportunities. Strengths so that they can do better in what they are good at, weeakness so that they improve. Threats so that they are aware on their environment and opportunities so that they go into unchattered grounds.