c. It takes time to gain the necessary experience
We need to consider how we measure what we have done. For example, someone could have had a pilot’s license for many years but only have flown enough hours to maintain their license whereas someone else could have flown a 1000 hours or more every year. Which one is likely to be the more experienced pilot? We would expect it to be the one who had done the most hours. Of course, other factors come into play such as the types of plane flown and the number of different airports visited or the number of different weather conditions experienced. Those are a bit more difficult to measure than hours.
Some experienced people have had the same experience again and again for years. Other people gain a wider range of experience by doing a variety of things for a shorter period. If we have been gaining experience on a part time basis then we are unlikely to make as much progress as someone who is working on a full time basis. In other words, time spent doing a task is one aspect of gaining experience.
On the other hand, our efforts could be more like that of a cart horse or a race horse. A race horse is quick but they soon tire and they cannot easily pull a load behind them. A cart horse plods along and does not move as fast as a race horse. However, a cart horse is built to move more things for a longer period of time so therefore can often achieve more during a day than a racehorse.