ROI, or Return on Investment, is a metric that shows the profitability of an investment as a percentage of the original amount invested. Arkmon ROI specifically refers to the Return on Investment since the time you began using Arkmon and linked your Kraken account. It focuses on the performance from that point onward.
On the other hand, normal ROI considers the entire history of your Kraken account, from the very start—even before you might have started using Arkmon. If you set up your Kraken account at the same time as beginning with Arkmon, then these two ROIs would be the same. Otherwise, they reflect different periods of your investment journey.