Why does dynamic multiselect search rerun when another input fieldvalue changes?

[matstap]

I have the following dynamic multiselect:

<input type="multiselect" token="carrier">
      <label>Carrier</label>
      <delimiter>, </delimiter>
      <fieldForLabel>CarrierName</fieldForLabel>
      <fieldForValue>CarrierID</fieldForValue>
      <search>
        <query>| inputlookup carrierlist.csv where 
    [| rest /services/authentication/current-context/context 
    | where username !="splunk-system-user" 
    | fields roles 
    | mvexpand roles 
    | join type=inner roles 
        [| inputlookup role_parent_carrier.csv ] 
    | table ParentCarrierID]</query>
      </search>
    </input>

Whenever I change the value of a custom input type, the dynamic search runs again and usually fails. Here is the definition of this custom date picker:

XML:

<input type="text" id="date_earliest" token="earliest">
      <label>Earliest</label>
    </input>
    <input type="text" id="date_latest" token="latest">
      <label>Latest</label>
    </input>

JS:

$("[id^=date]").attr('type', 'datetime-local');

$('#date_earliest').on('change', function(e) {
            var early = getEpoch($('input[id^=date_earliest]').val().replace(/(?<=[0-9])(T)/, " "));
            defaultTokenModel.set('earliest', early);
        });

        $('#date_latest').on('change', function(e) {
            var latest = getEpoch($('input[id^=date_latest]').val().replace(/(?<=[0-9])(T)/, " "));
            defaultTokenModel.set('latest', latest);
        });

Why are the .on('change'...) calls causing the search to run again?