comparison of subs vs. apply str butlast

gistfile1.txt

user=> (crit/bench (apply str (butlast "abcdefghijklmnopqrstuvwxyz")))
WARNING: Final GC required 1.1330059801880759 % of runtime
Evaluation count : 23463000 in 60 samples of 391050 calls.
             Execution time mean : 2.565453 µs
    Execution time std-deviation : 35.362281 ns
   Execution time lower quantile : 2.508671 µs ( 2.5%)
   Execution time upper quantile : 2.643954 µs (97.5%)
                   Overhead used : 1.563540 ns
nil
user=> (crit/bench (let [s "abcdefghijklmnopqrstuvwxyz"] (subs s 0 (max 0 (dec (count s))))))
WARNING: Final GC required 1.352930832614215 % of runtime
Evaluation count : 951202200 in 60 samples of 15853370 calls.
             Execution time mean : 62.722740 ns
    Execution time std-deviation : 0.805427 ns
   Execution time lower quantile : 61.060393 ns ( 2.5%)
   Execution time upper quantile : 63.973552 ns (97.5%)
                   Overhead used : 1.853935 ns
nil