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By default, the behavior of Vertical slider is min value should be in bottom position and max value should be in top position. If we invert the scale alignment it will be effect in slider value, ticks alignment and tooltip rendering. So it is not suggestable to invert the values in Slider.
If you want to customize the ticks as inverted scale, you can use the renderedTicks
custom event to achieve your requirement. To know more about the custom event, refer to the below link for example sample.
In this sample, we have customized the ticks as ‘Good’, ‘Excellent’ and so on.
Please let us know if you need further assistance on this.