Trading bots maybe useful for those newbie traders who have no idea of technical analysis. They may use crypto trading bots to do the trading for them because if they do it themselves they may incur more loss. But for the experienced traders, trading bots are not that useful because the human can better judge the market as compare to the artificial intelligence.
Their only use is automation of trades because it is not healthy for a human to stay awake for 24x7 and monitor the markets but let a bot do its job. Sleep is indeed the rest needed for every hardworking trader.
There are bots that can start an algorithm on detection of a specific market trigger preset by the owner, but these are more risky and the human judgement is obviously better here if this is being done by veteran traders. This should not be used by newbie traders because they could get washed away.
Then again there are those newbies who think they can use a bot and become a millionaire because of a false picture painted by some sellers. Nobody can help those people from parting with their money.