Experience will determine the level of success of a person in trading but I believe more that trading will have a time when someone gets a loss.
That applies at all times as you said and there are times when we lose and others win or vice versa.
But traders must understand how to recover losses in previous trades so that we are not trapped in continuous losses.
The only thing that can help recover losses is by understanding trading well so that knowledge combined with experience will provide an idea of how to recover.
But it must be remembered that trading only a few people succeed because if there is no knowledge or experience it is impossible for them to achieve success.
Experience will help traders to know importance of their trading capital and its protection. If they can defend their trading capital and more important initial trading capital, they are good traders. Traders can not say they are experienced because they have many years in the market, but practically they can not defend their trading capital. Experience with those traders means nothing and can not help them to even defend their capital, and can not help them to get more profit.
When you are in a market for longer time, you have more experience but if you can not learn from your experience to become a better trader, your experience is useless practically for you and your money. You will also have to consider of quitting your trading career because a bad trader will get more losses with time.