The accuracy column measures how close you got to the final version of the task.
Your accuracy may be high but this does not necessarily mean that your contribution will be high too if the text from which you started your work was already pretty good. Your contribution increases according to the amount of work you do in the task, by changing everything that is wrong, adding everything that is missing, and removing everything that is left over; and as long as your accuracy is high, of course.
There’s no point in making a lot of changes if they’re not right. Remember that the higher your accuracy and contribution, the more profits you’ll make. We recommend reading the instructions and doing the audio transcription tasks slowly and conscientiously so that you can train your hearing and you can achieve higher accuracy each time.