I am no linux expert but as far as I know, the IOWait percentage tells you the time the CPU is waiting for the IO to read/write. So what you are basically saying is that your CPU is 25% of its time waiting for your IO to finish.
As a result it most likely shows a high load (not a percentage, but a number) and a relatively low CPU usage percentage. The reason for that is that the instructions keep coming, but the CPU is patiently waiting for the IO to finish before it can start processing.
So simply said, the instruction “show lovelace” or “process login” is in the load queue, because the IO isn’t ready and the CPU is waiting.
FYI. My current average IOWait is about 0% since the switch to the SSD. The spikes I see are about once or twice an hour and hit 2% at most. CPU 3-6% and my 15m load average over a period of two hours is between 0.64 and 0.89
At the SD-Card times it was hitting 100% IOWaits as you can see in the image, even though I already had reduced the write actions.
I hope this helps.