Nevertheless, with pre-school education at an all-time high, representing virtually universal coverage, Scotland's pre-school providers are "generally very successful at ensuring that children are very well cared for".
In most cases, they ensure that children engage effectively in their learning. However, HMIE diagnoses that "in too many cases, inconsistencies and weaknesses are evident in key aspects of leadership", with significant weaknesses uncovered in about one in seven inspections.
Inspectors find a need for some improvement in the "quality of talk and interaction between adults and children to ensure that all children's learning needs are met fully".
The report adds: "In a significant number of centres, particularly in the private and voluntary sectors, the quality of leadership and of other factors dependent on leadership need to improve."
Key strengths identified by inspectors include relationships between staff and parents, and the commitment of staff and the increasing number who have qualifications. But staff need to improve various aspects of how they promote children's learning, particularly for those who require additional support.
In some centres, inspectors found that children did not have consistently good opportunities to develop skills of observation and investigation. In others, there was too much emphasis on adult-directed activities which limit their opportunities to encounter and solve problems in their learning.
The report states: "Overall, the quality of monitoring of children's learning experiences and the quality of self-evaluation more generally are still too inconsistent across the sector. In a significant minority of cases they are notably weak.
"In such instances, there is a lack of commitment among staff to genuine and productive professional reflection on their practice."