Error message in backoff process

Every time the back-off process runs, an error message appears.
Code: https://github.com/GoogleCloudPlatform/cloud-profiler-python/blob/bf96efa45005de10f0add920072c3803a5aa781e/googlecloudprofiler/client.py#L303-L316

I often get this error, but this is a little bit noisy (because I don't have to worry about it if a retry succeeds).

Ideally, I think, the error message should appear only after a certain number of trials or a certain elapsed time.

Do you have any plan to fix this?