You see, being a classical guitarist, I am used to the fingering shown in the image above. You will note that the left hand is numbered with index finger number 1, the middle 2 etc etc.
The right hand is different again with letters allocated to the fingers.
Now for the piano, of course, both hands have numbers allocated to the fingers but they are different to what I have been used to for the last 30 years or so.
The thumb is number 1 and the index 2 etc etc.
It is probably not quite such an issue for the right hand as I have not associated that with numbers but for the left it is definitely an issue and amplified by the fact I am still becoming accustomed to reading the bass clef. I look forward to a time in the future where I am instinctively using the correct finger!