The word "commitment" is too present in JIRA. This word represents one of the Scrum values since the last update of the Scrum Guide in July 2016.

It does not represent the objective of the Developement Team anymore and has been replaced since the 2011 version by the term "forecast": "The Development Team works to forecast the functionality that will be developed during the Sprint." The Development Team does not commit to an amount a stories, it forecasts by doing its best every day.

See the revisions of the Scrum Guide here: http://scrumguides.org/revisions.html

Wording is very important and mixing the terms disturb the comprehension that we have about things. Commitment is really an important word and by replacing it by forecast, we help all teams in the world understanding what it means to forecast a Sprint during the Sprint Planning!

Please note that the term is especially visible in the Velocity chart.

Thanks!