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At ten feet this is a very small tree or a good-size shrub. To actually keep it around ten feet, annual pruning will be required. When pruning, consider making thinning cuts that will replace any overly tall branches with new limbs each year. This will give the tree/shrub a more natural silhouette than hedging. If you want something with summer flowers, pruning should mostly be done in the Fall.
Is the planting site full to part sun? if so, consider English Laurel (Prunus laurocerasus) or for more showy flowers, perhaps Magnolia grandiflora 'Little Gem'. The blooms are spectacular, but flowering must be considered when deciding when and how to prune.
Of course, there are other options: evergreen privets (Ligustrum), hollies (Ilex), conifers. etc.
If the site is a shadier spot, consider a Rhododendron or Camellia. Flowers will mostly be in Spring, but beautiful all the same.