Unfortunately there are also problems related to this system, due to the increase in the network.
In recent years, Bitcoin and Ethereum have achieved sustained growth, both in terms of users but also in terms of transactions.
This means that if you have these increases, there is also the growth of the miners who, driven by requests for block validation, increase.
More miners leads to more difficulties on the network, it is more difficult leads to more energy required to solve the blockade.
In addition to this there is the fact that only one block at a time is solved by a single miningpool and all the others who participated remain empty-handed.
This leads to a waste of time and electricity costs.
This is why the system has been improved with the next generation of cripovalutes.
In this graph we can see how the difficulty has increased.