JMH - why JIT does not eliminate my dead-code

I wrote two benchmarks to demonstrate that JIT can be a problem with writing fine benchmark (Please skip that I doesnt use @State here):

@Fork(value = 1)
@Warmup(iterations = 2, time = 10)
@Measurement(iterations = 3, time = 2)
@BenchmarkMode(Mode.AverageTime)
public class DeadCodeTraps {

    @Benchmark
    @OutputTimeUnit(TimeUnit.MICROSECONDS)
    public static void summaryStatistics_standardDeviationForFourNumbers() {
        final SummaryStatistics summaryStatistics = new SummaryStatistics();
        summaryStatistics.addValue(10.0);
        summaryStatistics.addValue(20.0);
        summaryStatistics.addValue(30.0);
        summaryStatistics.addValue(40.0);
        summaryStatistics.getStandardDeviation();
    }

    @Benchmark
    @OutputTimeUnit(TimeUnit.MICROSECONDS)
    public static void summaryStatistics_standardDeviationForTenNumbers() {
        final SummaryStatistics summaryStatistics = new SummaryStatistics();
        summaryStatistics.addValue(10.0);
        summaryStatistics.addValue(20.0);
        summaryStatistics.addValue(30.0);
        summaryStatistics.addValue(40.0);
        summaryStatistics.addValue(50.0);
        summaryStatistics.addValue(60.0);
        summaryStatistics.addValue(70.0);
        summaryStatistics.addValue(80.0);
        summaryStatistics.addValue(90.0);
        summaryStatistics.addValue(100.0);
        summaryStatistics.getStandardDeviation();
    }

}

I thought that JIT will eliminate dead code, so two methods will be executed at the same time. But in the end, I have:

summaryStatistics_standardDeviationForFourNumbers 0.158 ± 0.046 DeadCodeTraps.summaryStatistics_standardDeviationForTenNumbers 0.359 ± 0.294

Why JIT does not optimize it? The result of summaryStatistics.getStandardDeviation(); is not used anywhere outside the method and it is not returned by it.

(I am using OpenJDK build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4)