Mining alone or solo is profitable, although the chances of succeeding in mining a block are minimal given that mining is highly based on luck. Instead, mining in a pool gives the high hash power you need and rewards you depending on the work that you have done.
However, before joining a pool, you should bear in mind the block reward distribution method and the fee levies charged for managing a pool. Furthermore, pools are important because they minimize the chances of cheating since individuals are barred from swapping the pools.
In order for someone to choose the best mining pool that corresponds to their needs, they need to know about some very important aspects: