Regardless of the rise or fall of the coin's price, the price movements on Spot and Perpetual Futures will be offset and incur no losses.
The return of spot-futures arbitrage is the funding rate minus trading fees of opening and closing positions. The drawdown of your investment is typically very low.
During the bull market, the funding rate is usually positive and high, the funding payment can be earned through short on perpetual futures in a spot-futures arbitrage.