The correct answer to this open question is the following.
If the business recommendation you are going to make in a business presentation is likely to be controversial, you should order the stem of your presentation hourglass so that the controversial issue comes after you have exposed the many benefits and advantages of your proposal. Doing this, people would have considered first the mane¿y advantages or positive points you previously mentioned and will be more open to considering the benefits against the disadvantages that create controversy.
Otherwise, if you do the opposite, the controversial issue is going to be at the top of their brains, hindering the acceptance of your business proposal.
Never start with the negatives because people could "close their minds" to your idea.