One of the biggest challenges that we will encounter in Bitcoin is the Scalability problem which means there is only limited amount of information that can be contained or its capacity. I'm sure that there will be more people who will going to join the campaign which will result to a possible delay during processing or trading. So how can we provide a solution on this or how to ensure that all the trading done were saved once delayed before bitcoin achieves mainstream adoption?
This has been an issue for some time and that is why the developers pushed for the activation of segwit which has alleviated the problem somehow but the real benefits of segwit are yet to come, the purpose of activating segwit was so the developers could release the Lightning Network once that is ready and it works as envisioned by the devs there will not be more scaling problems.