Don't just say "Thank you."
Finishing off by thanking the audience isn't bad in itself, but it won't give them a proper powerful experience at the end. To make your speech more effective, summarise the message in a few simple sentences and add some other useful steps the audience can take. Only then end your contribution with a "thank you".
You leave the ends open
Be sure to cover all the points you mention at the beginning. If you say you plan to go through four topics but then refer to only three, your audience will notice and, at the end, they will be so busy thinking about what happened to the last point, they will not remember the others.
If you happen briefly to forget the last point and then can't find a way to incorporate it smoothly, calmly announce you forgot something, but will now add it. The audience will appreciate the transparency and other information. And you will end your speech without omitting anything.
You do not use intonation and body language
An audience will perceive not only what you say, but also how you say it. Your tone of voice and intonation help signal the further development of your speech. Body language also plays a role here. For example, if you're in a physical space, you can hold some notes in your hand or summarise documents in one page. In a virtual environment, on the other hand, you can take a short break before the final announcement and then slightly raise your voice and deliver the final output with added emphasis. This tactic will attract the attention of the audience at the end of your presentation, which is exactly what you want.
You are missing a summary
The main theme of your presentation should be clear to everyone. Emphasise the main message to your audience. Every part of your speech should be relate back to the focal point. Make sure you are clear on how your sub-points support or relate to this main message. The end of your presentation should summarise the whole topic.
You forget the call to action
The purpose of the output is to get people to act. Think of your speech as a sales presentation. Decide what action your audience should take, and then get them to do it. It should be a strong and decisive statement. Be clear and direct.
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