Assertiveness/positiveness — the tendency or quality of acting proactively, taking initiative, and being willing to engage or propose ideas.
彼女は仕事に対して積極性があり、よく新しい案を出す。
She is proactive at work and often suggests new ideas.
採用ではスキルだけでなく積極性も評価の対象になった。
In hiring, not only skills but also assertiveness were evaluated.
会議では積極性を持って発言することが重要だ。
It's important to speak up proactively in meetings.