Bitcoin has 8 decimal places. So when the block reward gets halved, it adds a decimal place to block reward. 25 —> 12.5 —> 6.25 —> 3.125 —> 1.5625…—>0.09765625 The next halving will lose 0.000000005 bitcoin from the block reward due to precision limitation. Mathematically, the reward could be bigger. But in terms of computer memory, more decimal places means more memory. I highly doubt such precision will ever be necessary, but I’ve been wrong before.