The difficult I do immediately, the impossible takes a little bit longer.
Some reasons could be…

1. Using a DISTINCT clause
SELECT DISTINCT tblLifts.lLiftID AS LiftID, Sum(tblLifts.lGrossWeight) AS GrossWeight, Sum(tblLifts.lCalcNet) AS CalcNet, Sum([lGrossWeight]-[lCalcNet]) AS Tare
FROM tblLifts
GROUP BY tblLifts.lLiftID
ORDER BY tblLifts.lLiftID;
Unless you need your query to produce Unique Values, (see A) setting that to *No* will remove the DISTINCT clause
2. Use Aggregates, such as (see B)...
First, Last
Min, Max
StDev, StDevP
Var, VarP
SELECT Max(Val(Right$([msMetalLiftID],Len([msMetalLiftID])-InStr(1,[msMetalLiftID],"SS")-1))) AS LastBinID
FROM tblMetalScrap;
3. Applied formatting to a memo field, ie. Nz([ YourMemoField ]) or IIF()
Memo field is truncated when exported to Excel...