Clarify: SCS has to have a UI. Fixes #89

index.html

@@ -78,7 +78,7 @@ <h3 class="tile__heading-text">Own UI</h3>
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-			<p class="text-center">An SCS should make its features usable to end-users via its own UI. Therefore the SCS should have no shared UI with other SCSs. SCSs might still have links to each other. However, asynchronous integration means that the SCS should still work even if the UI of another SCS is not available.</p>
+			<p class="text-center">An SCS must make its features usable to end-users via its own UI. Therefore the SCS should have no shared UI with other SCSs. SCSs might still have links to each other. However, asynchronous integration means that the SCS should still work even if the UI of another SCS is not available.</p>
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 			<div class="tile__img-container"><img loading="lazy" src="img/characteristics-no-shared-business-logic.svg" alt="no shared business logic" class="benefit-image-customizable"></div>
@@ -373,4 +373,4 @@ <h2 class="text-centered">The Idea</h2>
 		Contribute on <a href="https://github.com/innoq/SCS">Github</a>.<br>
 		Find us on <a href="https://x.com/scsarchitecture">X (Twitter)</a>
 	</p>
-</section>
+</section>