The differentiation between Dev, Test and Live is a standard principle in software development that is useful for every kind of technical device.
You start the development on the dev stage, i.e. the stage in which your bot is in the least stable condition. In this stage you can identify major issues and quickly fix them. This is also the stage where your bots will always be deployed, so you don't accidentally deploy an unstable version to the live version of your bot.
Whenever you find your bot to be in a good condition, you promote it to the test stage where you can share your results with others and test it more generally. Now you can iron out the last problems, deploy them to dev and promote it to test. You should now go and test again to make sure to have a stable version that you can then promote to live.
The live stage is for the best version of your bot. It is a separate entity that is not being interfered by any other changes that you make in dev and test versions and will not be changed until you promote a new version. Only after a new promotion to live, your actual users will be able to see the changes that you made in the bot.
The idea behind it is that you are able to only present those products that you are completely happy with - and so will your users be.