Your reaction ran at 82.00% yield (1.8000 g lost from 10.0000 g theoretical).
You recovered 82.00% of the theoretical maximum, losing 18.00% (about 1.8000 g) in the process.
A good to very good yield for most laboratory transformations. Small improvements in transfer technique and purification can push this higher.
Common mechanical losses include product left on glassware during transfer, loss during recrystallization or extraction, and incomplete filtration. Each handling step reduces the final mass.
Next stepTo improve yield: minimise transfer steps, confirm the limiting reactant fully reacted, and optimise purification to retain more product.