Why intraday success rate declines when the cell sleep changes in network?

Hello Experts.

For the intra Handover success rate:

Why intraday success rate declines when the cell sleep changes in network?

A sleeping cell does not accept any incoming handovers so surrounding cells will have outgoing HO success rate degraded.

Will it have prep attempt or they will be not in that sleeping case?

Cell Sleep? Is it becasue of Power Saving features?

No, it is sleeping cell: no RRCs, no incoming handovers, nothing…

It’s a failure in the cell then, it must be reset.

Yes, Nokia had a lot of those cases in 3G, it turned a HW chip was doing this.

Don’t know how it is in 4G and 5G.

Yes, cell sleeping due to Power Saving feature.