Added clarification text on benchmark usefulness.
diff --git a/yotta/data/example-benchmark/README.md b/yotta/data/example-benchmark/README.md
index 1a534a2..8589e7b 100644
--- a/yotta/data/example-benchmark/README.md
+++ b/yotta/data/example-benchmark/README.md
@@ -92,3 +92,9 @@
{{success}}
{{end}}
```
+
+Any performance data generated by this example application are indicative only of the performance of the mbed TLS module on the platform it's executed on.
+
+Differences in the integration of mbed TLS into the platform, such as whether all available hardware accelerators have been used or not, can lead to significant differences in performance, and so results from the program are not intended to be used to meaningfully compare platforms.
+
+The figures may also slightly change from execution to execution due to variations in the timing functions.