Determined, firm or stubborn
Determined
Positive: not giving up on a goal.
Determined to learn to swim, Diya practised every morning.
Firm
Neutral to positive: not changing a fair decision.
The teacher was firm: no phones during the test.
Stubborn
Negative: refusing to change even when you should.
The stubborn goat would not move off the village road.
Remember: Same refusal to change, different feeling. Obstinate is a formal word close to stubborn.