improve comments

Author: Cecile Terpin

dd-trace-core/src/main/java/datadog/trace/core/traceinterceptor/LatencyTraceInterceptor.java

@@ -14,10 +14,11 @@
 // This value should be in milliseconds and this interceptor will retain any local trace who has a
 // root
 // span duration greater than this value.
-// The activation of this interceptor is ignored if partial flush is enabled.
+// The activation of this interceptor is ignored if partial flush is enabled in order to avoid
+// incomplete local trace (incomplete chunk of trace).
 // Note that since we're changing the sampling priority at the end of local trace, there is no
 // guarantee to get complete traces,
-// since the original sampling priority for this trace may have been already propagated.
+// since the original sampling priority for this trace may have already been propagated.
 
 public class LatencyTraceInterceptor extends AbstractTraceInterceptor {
   private static final Logger log = LoggerFactory.getLogger(LatencyTraceInterceptor.class);