Basic layout guidelines
This may appear to be so fundamental that it need not be written, but we're going to write it anyway. Content for slides need to be laid out from left to right or top to bottom.
There must be a good reason for deviating from this format. For example, an acceptable bottom-to-top flow would be building upward on a foundation. That would make sense.
When information is laid out in an illogical manner (right to left), your audience struggles to know what to focus on first: what is the message. If there is text on the left and on the right with an arrow in the middle pointing left, what do you read first? Avoid these ambiguities and check your slides for the basic left-to-right and top-to-bottom flow patterns.