Abu Huraira (may Allaah be pleased with him) said: the Messenger of Allaah (sallahAllaahu alayhi wasallam) said:
“Indeed a man prays for sixty years and his prayer is not accepted, perhaps he completes his Ruku (bowing) but he does not complete his Sujood (prostration) or completes his Sujood (prostration) but does not complete his Ruku.” 
The hadeeth informs of the great importance of having tranquility and completing properly the ruk’u and sujood, and not to rush. The consequence is great as you see.
Especially we need to point the common mistakes which people do in sujood:
– Leaving their feet hanging and not touching the ground = Your Sujood doesnt count = No prayer for you!
– Putting the forehead on the ground but not the nose = Your Sujood doesnt count = No prayer for you!
1.Silsilah as-Saheeha: 2535