Absolutely not. This is good on so many levels:
1) The Commission feel that they get more value for money – and that you were committed to the project.
2) If another partner under spends, and the consortium agree, then you could claim extra money.
2) If you have to do similar work in the future you can justify asking for more funding.
3) If you have an external audit and it is found that some of your eligible costs are actually ineligible, then you have more eligible costs to draw from.
These point are one of the things that we emphasise in our workshops.