What does the the optimisation option do in strategy backtest?

[ResoluteTrader]

   Hello,

I'm new to the community and to this realm of trading. So I'm having a bit of a learning curve with mt5/ mt4.

So I ran a backtest utilizing the mql5 cloud network, with my settings for the test set to slow complete algorithm. It was a simple RSI strategy, 1 year 5 minute timeframe. Was that necessary? Or did I just waste resources?