These are my  reasons
1. Has a larger market value among other cryptos
2. Being more in demand
3. High rate of increase on its market value
4. Profitable
5. I can't give more. Invest to Bitcoin if you are aiming for huge profit. You may read articles about how fast and big is its leap on its market value within jist a year particularly on this year. The increase is what gives its users especially investors huge profit since as the value is increasing the profit is getting bigger. And that's enough in my opinion to call Bitcoin a good investment.