Ads subtract

'X' is used to multiply
Exponents compact
A slash instructs you to divide
But every ad subtracts

I sit to watch a YouTube short —
The clip is seven seconds
But first a seven-minute ad
That takes about eleven

I finally get through that ordeal
Sure nothing could be worse
Until the influencer said,
"Let's discuss our sponsor first"

'X' is used to multiply
Exponents compact
A slash instructs you to divide
But every ad subtracts