The same planet differs by exaltation, debilitation, combustion, and retrograde.
Even the same Mars isn't always the same Mars. Depending on which Rashi it's in, it can express its strength comfortably at times, and in a tense way at others. This is called Dignity.
Let's start from the top. Exaltation (Uccha) is the placement where a planet expresses its strength at its brightest. Moolatrikona and Own Rashi (its own home) are also comfortable and stable. In the middle, neutral is neither especially strong nor weak. At the bottom, Debilitation (Neecha) means it works in a tense way, but that's exactly where it learns and grows the most. (Debilitation doesn't mean 'bad' — it's the difference between 'comfortable' and 'working hard.')
Besides dignity, there are two more things that change a planet's condition. One is Combustion (Asta) — when a planet sits too close to the Sun, it gets buried in the glare and struggles to make its own voice heard. The other is Retrograde — a period when a planet appears to move backward. Its strength turns inward, and works in a deeper, more reflective way.
So it's not simply, "Mars is there, so drive must be strong." You need to look at whether Mars is in its own Rashi, debilitated, combust from the Sun, or retrograde together to know its real strength. This is how you read the Navagraha one level deeper.
This content is for reference and entertainment, based on traditional Chinese metaphysics and astrology.